1 /* * Copyright (c) 2012-2016, The Tor Project, Inc. */
2 /* See LICENSE for licensing information */
7 * \brief OR/OP-to-OR channel abstraction layer. A channel's job is to
8 * transfer cells from Tor instance to Tor instance.
9 * Currently, there is only one implementation of the channel abstraction: in
14 * Define this so channel.h gives us things only channel_t subclasses
18 #define TOR_CHANNEL_INTERNAL_
20 /* This one's for stuff only channel.c and the test suite should see */
21 #define CHANNEL_PRIVATE_
25 #include "channeltls.h"
26 #include "circuitbuild.h"
27 #include "circuitlist.h"
28 #include "circuitstats.h"
30 #include "connection_or.h" /* For var_cell_free() */
31 #include "circuitmux.h"
32 #include "entrynodes.h"
38 #include "routerlist.h"
39 #include "scheduler.h"
41 /* Global lists of channels */
43 /* All channel_t instances */
44 static smartlist_t
*all_channels
= NULL
;
46 /* All channel_t instances not in ERROR or CLOSED states */
47 static smartlist_t
*active_channels
= NULL
;
49 /* All channel_t instances in ERROR or CLOSED states */
50 static smartlist_t
*finished_channels
= NULL
;
52 /* All channel_listener_t instances */
53 static smartlist_t
*all_listeners
= NULL
;
55 /* All channel_listener_t instances in LISTENING state */
56 static smartlist_t
*active_listeners
= NULL
;
58 /* All channel_listener_t instances in LISTENING state */
59 static smartlist_t
*finished_listeners
= NULL
;
61 /* Counter for ID numbers */
62 static uint64_t n_channels_allocated
= 0;
64 * Channel global byte/cell counters, for statistics and for scheduler high
69 * Total number of cells ever given to any channel with the
70 * channel_write_*_cell() functions.
73 static uint64_t n_channel_cells_queued
= 0;
76 * Total number of cells ever passed to a channel lower layer with the
77 * write_*_cell() methods.
80 static uint64_t n_channel_cells_passed_to_lower_layer
= 0;
83 * Current number of cells in all channel queues; should be
84 * n_channel_cells_queued - n_channel_cells_passed_to_lower_layer.
87 static uint64_t n_channel_cells_in_queues
= 0;
90 * Total number of bytes for all cells ever queued to a channel and
91 * counted in n_channel_cells_queued.
94 static uint64_t n_channel_bytes_queued
= 0;
97 * Total number of bytes for all cells ever passed to a channel lower layer
98 * and counted in n_channel_cells_passed_to_lower_layer.
101 static uint64_t n_channel_bytes_passed_to_lower_layer
= 0;
104 * Current number of bytes in all channel queues; should be
105 * n_channel_bytes_queued - n_channel_bytes_passed_to_lower_layer.
108 static uint64_t n_channel_bytes_in_queues
= 0;
111 * Current total estimated queue size *including lower layer queues and
115 STATIC
uint64_t estimated_total_queue_size
= 0;
117 /* Digest->channel map
119 * Similar to the one used in connection_or.c, this maps from the identity
120 * digest of a remote endpoint to a channel_t to that endpoint. Channels
121 * should be placed here when registered and removed when they close or error.
122 * If more than one channel exists, follow the next_with_same_id pointer
125 static HT_HEAD(channel_idmap
, channel_idmap_entry_s
) channel_identity_map
=
128 typedef struct channel_idmap_entry_s
{
129 HT_ENTRY(channel_idmap_entry_s
) node
;
130 uint8_t digest
[DIGEST_LEN
];
131 TOR_LIST_HEAD(channel_list_s
, channel_s
) channel_list
;
132 } channel_idmap_entry_t
;
134 static inline unsigned
135 channel_idmap_hash(const channel_idmap_entry_t
*ent
)
137 return (unsigned) siphash24g(ent
->digest
, DIGEST_LEN
);
141 channel_idmap_eq(const channel_idmap_entry_t
*a
,
142 const channel_idmap_entry_t
*b
)
144 return tor_memeq(a
->digest
, b
->digest
, DIGEST_LEN
);
147 HT_PROTOTYPE(channel_idmap
, channel_idmap_entry_s
, node
, channel_idmap_hash
,
149 HT_GENERATE2(channel_idmap
, channel_idmap_entry_s
, node
, channel_idmap_hash
,
150 channel_idmap_eq
, 0.5, tor_reallocarray_
, tor_free_
)
152 static cell_queue_entry_t
* cell_queue_entry_dup(cell_queue_entry_t
*q
);
154 static int cell_queue_entry_is_padding(cell_queue_entry_t
*q
);
156 static cell_queue_entry_t
*
157 cell_queue_entry_new_fixed(cell_t
*cell
);
158 static cell_queue_entry_t
*
159 cell_queue_entry_new_var(var_cell_t
*var_cell
);
160 static int is_destroy_cell(channel_t
*chan
,
161 const cell_queue_entry_t
*q
, circid_t
*circid_out
);
163 static void channel_assert_counter_consistency(void);
165 /* Functions to maintain the digest map */
166 static void channel_add_to_digest_map(channel_t
*chan
);
167 static void channel_remove_from_digest_map(channel_t
*chan
);
170 * Flush cells from just the outgoing queue without trying to get them
171 * from circuits; used internall by channel_flush_some_cells().
174 channel_flush_some_cells_from_outgoing_queue(channel_t
*chan
,
176 static void channel_force_free(channel_t
*chan
);
178 channel_free_list(smartlist_t
*channels
, int mark_for_close
);
180 channel_listener_free_list(smartlist_t
*channels
, int mark_for_close
);
181 static void channel_listener_force_free(channel_listener_t
*chan_l
);
182 static size_t channel_get_cell_queue_entry_size(channel_t
*chan
,
183 cell_queue_entry_t
*q
);
185 channel_write_cell_queue_entry(channel_t
*chan
, cell_queue_entry_t
*q
);
187 /***********************************
188 * Channel state utility functions *
189 **********************************/
192 * Indicate whether a given channel state is valid
196 channel_state_is_valid(channel_state_t state
)
201 case CHANNEL_STATE_CLOSED
:
202 case CHANNEL_STATE_CLOSING
:
203 case CHANNEL_STATE_ERROR
:
204 case CHANNEL_STATE_MAINT
:
205 case CHANNEL_STATE_OPENING
:
206 case CHANNEL_STATE_OPEN
:
209 case CHANNEL_STATE_LAST
:
218 * Indicate whether a given channel listener state is valid
222 channel_listener_state_is_valid(channel_listener_state_t state
)
227 case CHANNEL_LISTENER_STATE_CLOSED
:
228 case CHANNEL_LISTENER_STATE_LISTENING
:
229 case CHANNEL_LISTENER_STATE_CLOSING
:
230 case CHANNEL_LISTENER_STATE_ERROR
:
233 case CHANNEL_LISTENER_STATE_LAST
:
242 * Indicate whether a channel state transition is valid
244 * This function takes two channel states and indicates whether a
245 * transition between them is permitted (see the state definitions and
246 * transition table in or.h at the channel_state_t typedef).
250 channel_state_can_transition(channel_state_t from
, channel_state_t to
)
255 case CHANNEL_STATE_CLOSED
:
256 is_valid
= (to
== CHANNEL_STATE_OPENING
);
258 case CHANNEL_STATE_CLOSING
:
259 is_valid
= (to
== CHANNEL_STATE_CLOSED
||
260 to
== CHANNEL_STATE_ERROR
);
262 case CHANNEL_STATE_ERROR
:
265 case CHANNEL_STATE_MAINT
:
266 is_valid
= (to
== CHANNEL_STATE_CLOSING
||
267 to
== CHANNEL_STATE_ERROR
||
268 to
== CHANNEL_STATE_OPEN
);
270 case CHANNEL_STATE_OPENING
:
271 is_valid
= (to
== CHANNEL_STATE_CLOSING
||
272 to
== CHANNEL_STATE_ERROR
||
273 to
== CHANNEL_STATE_OPEN
);
275 case CHANNEL_STATE_OPEN
:
276 is_valid
= (to
== CHANNEL_STATE_CLOSING
||
277 to
== CHANNEL_STATE_ERROR
||
278 to
== CHANNEL_STATE_MAINT
);
280 case CHANNEL_STATE_LAST
:
289 * Indicate whether a channel listener state transition is valid
291 * This function takes two channel listener states and indicates whether a
292 * transition between them is permitted (see the state definitions and
293 * transition table in or.h at the channel_listener_state_t typedef).
297 channel_listener_state_can_transition(channel_listener_state_t from
,
298 channel_listener_state_t to
)
303 case CHANNEL_LISTENER_STATE_CLOSED
:
304 is_valid
= (to
== CHANNEL_LISTENER_STATE_LISTENING
);
306 case CHANNEL_LISTENER_STATE_CLOSING
:
307 is_valid
= (to
== CHANNEL_LISTENER_STATE_CLOSED
||
308 to
== CHANNEL_LISTENER_STATE_ERROR
);
310 case CHANNEL_LISTENER_STATE_ERROR
:
313 case CHANNEL_LISTENER_STATE_LISTENING
:
314 is_valid
= (to
== CHANNEL_LISTENER_STATE_CLOSING
||
315 to
== CHANNEL_LISTENER_STATE_ERROR
);
317 case CHANNEL_LISTENER_STATE_LAST
:
326 * Return a human-readable description for a channel state
330 channel_state_to_string(channel_state_t state
)
335 case CHANNEL_STATE_CLOSED
:
338 case CHANNEL_STATE_CLOSING
:
341 case CHANNEL_STATE_ERROR
:
342 descr
= "channel error";
344 case CHANNEL_STATE_MAINT
:
345 descr
= "temporarily suspended for maintenance";
347 case CHANNEL_STATE_OPENING
:
350 case CHANNEL_STATE_OPEN
:
353 case CHANNEL_STATE_LAST
:
355 descr
= "unknown or invalid channel state";
362 * Return a human-readable description for a channel listenier state
366 channel_listener_state_to_string(channel_listener_state_t state
)
371 case CHANNEL_LISTENER_STATE_CLOSED
:
374 case CHANNEL_LISTENER_STATE_CLOSING
:
377 case CHANNEL_LISTENER_STATE_ERROR
:
378 descr
= "channel listener error";
380 case CHANNEL_LISTENER_STATE_LISTENING
:
383 case CHANNEL_LISTENER_STATE_LAST
:
385 descr
= "unknown or invalid channel listener state";
391 /***************************************
392 * Channel registration/unregistration *
393 ***************************************/
398 * This function registers a newly created channel in the global lists/maps
399 * of active channels.
403 channel_register(channel_t
*chan
)
407 /* No-op if already registered */
408 if (chan
->registered
) return;
410 log_debug(LD_CHANNEL
,
411 "Registering channel %p (ID " U64_FORMAT
") "
412 "in state %s (%d) with digest %s",
413 chan
, U64_PRINTF_ARG(chan
->global_identifier
),
414 channel_state_to_string(chan
->state
), chan
->state
,
415 hex_str(chan
->identity_digest
, DIGEST_LEN
));
417 /* Make sure we have all_channels, then add it */
418 if (!all_channels
) all_channels
= smartlist_new();
419 smartlist_add(all_channels
, chan
);
421 /* Is it finished? */
422 if (CHANNEL_FINISHED(chan
)) {
423 /* Put it in the finished list, creating it if necessary */
424 if (!finished_channels
) finished_channels
= smartlist_new();
425 smartlist_add(finished_channels
, chan
);
427 /* Put it in the active list, creating it if necessary */
428 if (!active_channels
) active_channels
= smartlist_new();
429 smartlist_add(active_channels
, chan
);
431 if (!CHANNEL_IS_CLOSING(chan
)) {
432 /* It should have a digest set */
433 if (!tor_digest_is_zero(chan
->identity_digest
)) {
434 /* Yeah, we're good, add it to the map */
435 channel_add_to_digest_map(chan
);
438 "Channel %p (global ID " U64_FORMAT
") "
439 "in state %s (%d) registered with no identity digest",
440 chan
, U64_PRINTF_ARG(chan
->global_identifier
),
441 channel_state_to_string(chan
->state
), chan
->state
);
446 /* Mark it as registered */
447 chan
->registered
= 1;
451 * Unregister a channel
453 * This function removes a channel from the global lists and maps and is used
454 * when freeing a closed/errored channel.
458 channel_unregister(channel_t
*chan
)
462 /* No-op if not registered */
463 if (!(chan
->registered
)) return;
465 /* Is it finished? */
466 if (CHANNEL_FINISHED(chan
)) {
467 /* Get it out of the finished list */
468 if (finished_channels
) smartlist_remove(finished_channels
, chan
);
470 /* Get it out of the active list */
471 if (active_channels
) smartlist_remove(active_channels
, chan
);
474 /* Get it out of all_channels */
475 if (all_channels
) smartlist_remove(all_channels
, chan
);
477 /* Mark it as unregistered */
478 chan
->registered
= 0;
480 /* Should it be in the digest map? */
481 if (!tor_digest_is_zero(chan
->identity_digest
) &&
482 !(CHANNEL_CONDEMNED(chan
))) {
484 channel_remove_from_digest_map(chan
);
489 * Register a channel listener
491 * This function registers a newly created channel listner in the global
492 * lists/maps of active channel listeners.
496 channel_listener_register(channel_listener_t
*chan_l
)
500 /* No-op if already registered */
501 if (chan_l
->registered
) return;
503 log_debug(LD_CHANNEL
,
504 "Registering channel listener %p (ID " U64_FORMAT
") "
506 chan_l
, U64_PRINTF_ARG(chan_l
->global_identifier
),
507 channel_listener_state_to_string(chan_l
->state
),
510 /* Make sure we have all_channels, then add it */
511 if (!all_listeners
) all_listeners
= smartlist_new();
512 smartlist_add(all_listeners
, chan_l
);
514 /* Is it finished? */
515 if (chan_l
->state
== CHANNEL_LISTENER_STATE_CLOSED
||
516 chan_l
->state
== CHANNEL_LISTENER_STATE_ERROR
) {
517 /* Put it in the finished list, creating it if necessary */
518 if (!finished_listeners
) finished_listeners
= smartlist_new();
519 smartlist_add(finished_listeners
, chan_l
);
521 /* Put it in the active list, creating it if necessary */
522 if (!active_listeners
) active_listeners
= smartlist_new();
523 smartlist_add(active_listeners
, chan_l
);
526 /* Mark it as registered */
527 chan_l
->registered
= 1;
531 * Unregister a channel listener
533 * This function removes a channel listener from the global lists and maps
534 * and is used when freeing a closed/errored channel listener.
538 channel_listener_unregister(channel_listener_t
*chan_l
)
542 /* No-op if not registered */
543 if (!(chan_l
->registered
)) return;
545 /* Is it finished? */
546 if (chan_l
->state
== CHANNEL_LISTENER_STATE_CLOSED
||
547 chan_l
->state
== CHANNEL_LISTENER_STATE_ERROR
) {
548 /* Get it out of the finished list */
549 if (finished_listeners
) smartlist_remove(finished_listeners
, chan_l
);
551 /* Get it out of the active list */
552 if (active_listeners
) smartlist_remove(active_listeners
, chan_l
);
555 /* Get it out of all_channels */
556 if (all_listeners
) smartlist_remove(all_listeners
, chan_l
);
558 /* Mark it as unregistered */
559 chan_l
->registered
= 0;
562 /*********************************
563 * Channel digest map maintenance
564 *********************************/
567 * Add a channel to the digest map
569 * This function adds a channel to the digest map and inserts it into the
570 * correct linked list if channels with that remote endpoint identity digest
575 channel_add_to_digest_map(channel_t
*chan
)
577 channel_idmap_entry_t
*ent
, search
;
581 /* Assert that the state makes sense */
582 tor_assert(!CHANNEL_CONDEMNED(chan
));
584 /* Assert that there is a digest */
585 tor_assert(!tor_digest_is_zero(chan
->identity_digest
));
587 memcpy(search
.digest
, chan
->identity_digest
, DIGEST_LEN
);
588 ent
= HT_FIND(channel_idmap
, &channel_identity_map
, &search
);
590 ent
= tor_malloc(sizeof(channel_idmap_entry_t
));
591 memcpy(ent
->digest
, chan
->identity_digest
, DIGEST_LEN
);
592 TOR_LIST_INIT(&ent
->channel_list
);
593 HT_INSERT(channel_idmap
, &channel_identity_map
, ent
);
595 TOR_LIST_INSERT_HEAD(&ent
->channel_list
, chan
, next_with_same_id
);
597 log_debug(LD_CHANNEL
,
598 "Added channel %p (global ID " U64_FORMAT
") "
599 "to identity map in state %s (%d) with digest %s",
600 chan
, U64_PRINTF_ARG(chan
->global_identifier
),
601 channel_state_to_string(chan
->state
), chan
->state
,
602 hex_str(chan
->identity_digest
, DIGEST_LEN
));
606 * Remove a channel from the digest map
608 * This function removes a channel from the digest map and the linked list of
609 * channels for that digest if more than one exists.
613 channel_remove_from_digest_map(channel_t
*chan
)
615 channel_idmap_entry_t
*ent
, search
;
619 /* Assert that there is a digest */
620 tor_assert(!tor_digest_is_zero(chan
->identity_digest
));
623 /* Make sure we have a map */
624 if (!channel_identity_map
) {
626 * No identity map, so we can't find it by definition. This
627 * case is similar to digestmap_get() failing below.
630 "Trying to remove channel %p (global ID " U64_FORMAT
") "
631 "with digest %s from identity map, but didn't have any identity "
633 chan
, U64_PRINTF_ARG(chan
->global_identifier
),
634 hex_str(chan
->identity_digest
, DIGEST_LEN
));
635 /* Clear out its next/prev pointers */
636 if (chan
->next_with_same_id
) {
637 chan
->next_with_same_id
->prev_with_same_id
= chan
->prev_with_same_id
;
639 if (chan
->prev_with_same_id
) {
640 chan
->prev_with_same_id
->next_with_same_id
= chan
->next_with_same_id
;
642 chan
->next_with_same_id
= NULL
;
643 chan
->prev_with_same_id
= NULL
;
649 /* Pull it out of its list, wherever that list is */
650 TOR_LIST_REMOVE(chan
, next_with_same_id
);
652 memcpy(search
.digest
, chan
->identity_digest
, DIGEST_LEN
);
653 ent
= HT_FIND(channel_idmap
, &channel_identity_map
, &search
);
655 /* Look for it in the map */
657 /* Okay, it's here */
659 if (TOR_LIST_EMPTY(&ent
->channel_list
)) {
660 HT_REMOVE(channel_idmap
, &channel_identity_map
, ent
);
664 log_debug(LD_CHANNEL
,
665 "Removed channel %p (global ID " U64_FORMAT
") from "
666 "identity map in state %s (%d) with digest %s",
667 chan
, U64_PRINTF_ARG(chan
->global_identifier
),
668 channel_state_to_string(chan
->state
), chan
->state
,
669 hex_str(chan
->identity_digest
, DIGEST_LEN
));
671 /* Shouldn't happen */
673 "Trying to remove channel %p (global ID " U64_FORMAT
") with "
674 "digest %s from identity map, but couldn't find any with "
676 chan
, U64_PRINTF_ARG(chan
->global_identifier
),
677 hex_str(chan
->identity_digest
, DIGEST_LEN
));
681 /****************************
682 * Channel lookup functions *
683 ***************************/
686 * Find channel by global ID
688 * This function searches for a channel by the global_identifier assigned
689 * at initialization time. This identifier is unique for the lifetime of the
694 channel_find_by_global_id(uint64_t global_identifier
)
696 channel_t
*rv
= NULL
;
698 if (all_channels
&& smartlist_len(all_channels
) > 0) {
699 SMARTLIST_FOREACH_BEGIN(all_channels
, channel_t
*, curr
) {
700 if (curr
->global_identifier
== global_identifier
) {
704 } SMARTLIST_FOREACH_END(curr
);
711 * Find channel by digest of the remote endpoint
713 * This function looks up a channel by the digest of its remote endpoint in
714 * the channel digest map. It's possible that more than one channel to a
715 * given endpoint exists. Use channel_next_with_digest() to walk the list.
719 channel_find_by_remote_digest(const char *identity_digest
)
721 channel_t
*rv
= NULL
;
722 channel_idmap_entry_t
*ent
, search
;
724 tor_assert(identity_digest
);
726 memcpy(search
.digest
, identity_digest
, DIGEST_LEN
);
727 ent
= HT_FIND(channel_idmap
, &channel_identity_map
, &search
);
729 rv
= TOR_LIST_FIRST(&ent
->channel_list
);
736 * Get next channel with digest
738 * This function takes a channel and finds the next channel in the list
739 * with the same digest.
743 channel_next_with_digest(channel_t
*chan
)
747 return TOR_LIST_NEXT(chan
, next_with_same_id
);
751 * Initialize a channel
753 * This function should be called by subclasses to set up some per-channel
754 * variables. I.e., this is the superclass constructor. Before this, the
755 * channel should be allocated with tor_malloc_zero().
759 channel_init(channel_t
*chan
)
763 /* Assign an ID and bump the counter */
764 chan
->global_identifier
= n_channels_allocated
++;
767 chan
->timestamp_last_had_circuits
= time(NULL
);
769 /* Warn about exhausted circuit IDs no more than hourly. */
770 chan
->last_warned_circ_ids_exhausted
.rate
= 3600;
772 /* Initialize queues. */
773 TOR_SIMPLEQ_INIT(&chan
->incoming_queue
);
774 TOR_SIMPLEQ_INIT(&chan
->outgoing_queue
);
776 /* Initialize list entries. */
777 memset(&chan
->next_with_same_id
, 0, sizeof(chan
->next_with_same_id
));
780 channel_timestamp_created(chan
);
782 /* It hasn't been open yet. */
783 chan
->has_been_open
= 0;
785 /* Scheduler state is idle */
786 chan
->scheduler_state
= SCHED_CHAN_IDLE
;
790 * Initialize a channel listener
792 * This function should be called by subclasses to set up some per-channel
793 * variables. I.e., this is the superclass constructor. Before this, the
794 * channel listener should be allocated with tor_malloc_zero().
798 channel_init_listener(channel_listener_t
*chan_l
)
802 /* Assign an ID and bump the counter */
803 chan_l
->global_identifier
= n_channels_allocated
++;
806 channel_listener_timestamp_created(chan_l
);
810 * Free a channel; nothing outside of channel.c and subclasses should call
811 * this - it frees channels after they have closed and been unregistered.
815 channel_free(channel_t
*chan
)
819 /* It must be closed or errored */
820 tor_assert(CHANNEL_FINISHED(chan
));
822 /* It must be deregistered */
823 tor_assert(!(chan
->registered
));
825 log_debug(LD_CHANNEL
,
826 "Freeing channel " U64_FORMAT
" at %p",
827 U64_PRINTF_ARG(chan
->global_identifier
), chan
);
829 /* Get this one out of the scheduler */
830 scheduler_release_channel(chan
);
833 * Get rid of cmux policy before we do anything, so cmux policies don't
834 * see channels in weird half-freed states.
837 circuitmux_set_policy(chan
->cmux
, NULL
);
840 /* Call a free method if there is one */
841 if (chan
->free
) chan
->free(chan
);
843 channel_clear_remote_end(chan
);
845 /* Get rid of cmux */
847 circuitmux_detach_all_circuits(chan
->cmux
, NULL
);
848 circuitmux_mark_destroyed_circids_usable(chan
->cmux
, chan
);
849 circuitmux_free(chan
->cmux
);
853 /* We're in CLOSED or ERROR, so the cell queue is already empty */
859 * Free a channel listener; nothing outside of channel.c and subclasses
860 * should call this - it frees channel listeners after they have closed and
865 channel_listener_free(channel_listener_t
*chan_l
)
869 log_debug(LD_CHANNEL
,
870 "Freeing channel_listener_t " U64_FORMAT
" at %p",
871 U64_PRINTF_ARG(chan_l
->global_identifier
),
874 /* It must be closed or errored */
875 tor_assert(chan_l
->state
== CHANNEL_LISTENER_STATE_CLOSED
||
876 chan_l
->state
== CHANNEL_LISTENER_STATE_ERROR
);
877 /* It must be deregistered */
878 tor_assert(!(chan_l
->registered
));
880 /* Call a free method if there is one */
881 if (chan_l
->free
) chan_l
->free(chan_l
);
884 * We're in CLOSED or ERROR, so the incoming channel queue is already
892 * Free a channel and skip the state/registration asserts; this internal-
893 * use-only function should be called only from channel_free_all() when
894 * shutting down the Tor process.
898 channel_force_free(channel_t
*chan
)
900 cell_queue_entry_t
*cell
, *cell_tmp
;
903 log_debug(LD_CHANNEL
,
904 "Force-freeing channel " U64_FORMAT
" at %p",
905 U64_PRINTF_ARG(chan
->global_identifier
), chan
);
907 /* Get this one out of the scheduler */
908 scheduler_release_channel(chan
);
911 * Get rid of cmux policy before we do anything, so cmux policies don't
912 * see channels in weird half-freed states.
915 circuitmux_set_policy(chan
->cmux
, NULL
);
918 /* Call a free method if there is one */
919 if (chan
->free
) chan
->free(chan
);
921 channel_clear_remote_end(chan
);
923 /* Get rid of cmux */
925 circuitmux_free(chan
->cmux
);
929 /* We might still have a cell queue; kill it */
930 TOR_SIMPLEQ_FOREACH_SAFE(cell
, &chan
->incoming_queue
, next
, cell_tmp
) {
931 cell_queue_entry_free(cell
, 0);
933 TOR_SIMPLEQ_INIT(&chan
->incoming_queue
);
935 /* Outgoing cell queue is similar, but we can have to free packed cells */
936 TOR_SIMPLEQ_FOREACH_SAFE(cell
, &chan
->outgoing_queue
, next
, cell_tmp
) {
937 cell_queue_entry_free(cell
, 0);
939 TOR_SIMPLEQ_INIT(&chan
->outgoing_queue
);
945 * Free a channel listener and skip the state/reigstration asserts; this
946 * internal-use-only function should be called only from channel_free_all()
947 * when shutting down the Tor process.
951 channel_listener_force_free(channel_listener_t
*chan_l
)
955 log_debug(LD_CHANNEL
,
956 "Force-freeing channel_listener_t " U64_FORMAT
" at %p",
957 U64_PRINTF_ARG(chan_l
->global_identifier
),
960 /* Call a free method if there is one */
961 if (chan_l
->free
) chan_l
->free(chan_l
);
964 * The incoming list just gets emptied and freed; we request close on
965 * any channels we find there, but since we got called while shutting
966 * down they will get deregistered and freed elsewhere anyway.
968 if (chan_l
->incoming_list
) {
969 SMARTLIST_FOREACH_BEGIN(chan_l
->incoming_list
,
970 channel_t
*, qchan
) {
971 channel_mark_for_close(qchan
);
972 } SMARTLIST_FOREACH_END(qchan
);
974 smartlist_free(chan_l
->incoming_list
);
975 chan_l
->incoming_list
= NULL
;
982 * Return the current registered listener for a channel listener
984 * This function returns a function pointer to the current registered
985 * handler for new incoming channels on a channel listener.
988 channel_listener_fn_ptr
989 channel_listener_get_listener_fn(channel_listener_t
*chan_l
)
993 if (chan_l
->state
== CHANNEL_LISTENER_STATE_LISTENING
)
994 return chan_l
->listener
;
1000 * Set the listener for a channel listener
1002 * This function sets the handler for new incoming channels on a channel
1007 channel_listener_set_listener_fn(channel_listener_t
*chan_l
,
1008 channel_listener_fn_ptr listener
)
1011 tor_assert(chan_l
->state
== CHANNEL_LISTENER_STATE_LISTENING
);
1013 log_debug(LD_CHANNEL
,
1014 "Setting listener callback for channel listener %p "
1015 "(global ID " U64_FORMAT
") to %p",
1016 chan_l
, U64_PRINTF_ARG(chan_l
->global_identifier
),
1019 chan_l
->listener
= listener
;
1020 if (chan_l
->listener
) channel_listener_process_incoming(chan_l
);
1024 * Return the fixed-length cell handler for a channel
1026 * This function gets the handler for incoming fixed-length cells installed
1030 channel_cell_handler_fn_ptr
1031 channel_get_cell_handler(channel_t
*chan
)
1035 if (CHANNEL_CAN_HANDLE_CELLS(chan
))
1036 return chan
->cell_handler
;
1042 * Return the variable-length cell handler for a channel
1044 * This function gets the handler for incoming variable-length cells
1045 * installed on a channel.
1048 channel_var_cell_handler_fn_ptr
1049 channel_get_var_cell_handler(channel_t
*chan
)
1053 if (CHANNEL_CAN_HANDLE_CELLS(chan
))
1054 return chan
->var_cell_handler
;
1060 * Set both cell handlers for a channel
1062 * This function sets both the fixed-length and variable length cell handlers
1063 * for a channel and processes any incoming cells that had been blocked in the
1064 * queue because none were available.
1068 channel_set_cell_handlers(channel_t
*chan
,
1069 channel_cell_handler_fn_ptr cell_handler
,
1070 channel_var_cell_handler_fn_ptr
1076 tor_assert(CHANNEL_CAN_HANDLE_CELLS(chan
));
1078 log_debug(LD_CHANNEL
,
1079 "Setting cell_handler callback for channel %p to %p",
1080 chan
, cell_handler
);
1081 log_debug(LD_CHANNEL
,
1082 "Setting var_cell_handler callback for channel %p to %p",
1083 chan
, var_cell_handler
);
1085 /* Should we try the queue? */
1087 cell_handler
!= chan
->cell_handler
) try_again
= 1;
1088 if (var_cell_handler
&&
1089 var_cell_handler
!= chan
->var_cell_handler
) try_again
= 1;
1092 chan
->cell_handler
= cell_handler
;
1093 chan
->var_cell_handler
= var_cell_handler
;
1095 /* Re-run the queue if we have one and there's any reason to */
1096 if (! TOR_SIMPLEQ_EMPTY(&chan
->incoming_queue
) &&
1098 (chan
->cell_handler
||
1099 chan
->var_cell_handler
)) channel_process_cells(chan
);
1103 * On closing channels
1105 * There are three functions that close channels, for use in
1106 * different circumstances:
1108 * - Use channel_mark_for_close() for most cases
1109 * - Use channel_close_from_lower_layer() if you are connection_or.c
1110 * and the other end closes the underlying connection.
1111 * - Use channel_close_for_error() if you are connection_or.c and
1112 * some sort of error has occurred.
1116 * Mark a channel for closure
1118 * This function tries to close a channel_t; it will go into the CLOSING
1119 * state, and eventually the lower layer should put it into the CLOSED or
1120 * ERROR state. Then, channel_run_cleanup() will eventually free it.
1124 channel_mark_for_close(channel_t
*chan
)
1126 tor_assert(chan
!= NULL
);
1127 tor_assert(chan
->close
!= NULL
);
1129 /* If it's already in CLOSING, CLOSED or ERROR, this is a no-op */
1130 if (CHANNEL_CONDEMNED(chan
))
1133 log_debug(LD_CHANNEL
,
1134 "Closing channel %p (global ID " U64_FORMAT
") "
1136 chan
, U64_PRINTF_ARG(chan
->global_identifier
));
1138 /* Note closing by request from above */
1139 chan
->reason_for_closing
= CHANNEL_CLOSE_REQUESTED
;
1141 /* Change state to CLOSING */
1142 channel_change_state(chan
, CHANNEL_STATE_CLOSING
);
1144 /* Tell the lower layer */
1148 * It's up to the lower layer to change state to CLOSED or ERROR when we're
1149 * ready; we'll try to free channels that are in the finished list from
1150 * channel_run_cleanup(). The lower layer should do this by calling
1156 * Mark a channel listener for closure
1158 * This function tries to close a channel_listener_t; it will go into the
1159 * CLOSING state, and eventually the lower layer should put it into the CLOSED
1160 * or ERROR state. Then, channel_run_cleanup() will eventually free it.
1164 channel_listener_mark_for_close(channel_listener_t
*chan_l
)
1166 tor_assert(chan_l
!= NULL
);
1167 tor_assert(chan_l
->close
!= NULL
);
1169 /* If it's already in CLOSING, CLOSED or ERROR, this is a no-op */
1170 if (chan_l
->state
== CHANNEL_LISTENER_STATE_CLOSING
||
1171 chan_l
->state
== CHANNEL_LISTENER_STATE_CLOSED
||
1172 chan_l
->state
== CHANNEL_LISTENER_STATE_ERROR
) return;
1174 log_debug(LD_CHANNEL
,
1175 "Closing channel listener %p (global ID " U64_FORMAT
") "
1177 chan_l
, U64_PRINTF_ARG(chan_l
->global_identifier
));
1179 /* Note closing by request from above */
1180 chan_l
->reason_for_closing
= CHANNEL_LISTENER_CLOSE_REQUESTED
;
1182 /* Change state to CLOSING */
1183 channel_listener_change_state(chan_l
, CHANNEL_LISTENER_STATE_CLOSING
);
1185 /* Tell the lower layer */
1186 chan_l
->close(chan_l
);
1189 * It's up to the lower layer to change state to CLOSED or ERROR when we're
1190 * ready; we'll try to free channels that are in the finished list from
1191 * channel_run_cleanup(). The lower layer should do this by calling
1192 * channel_listener_closed().
1197 * Close a channel from the lower layer
1199 * Notify the channel code that the channel is being closed due to a non-error
1200 * condition in the lower layer. This does not call the close() method, since
1201 * the lower layer already knows.
1205 channel_close_from_lower_layer(channel_t
*chan
)
1207 tor_assert(chan
!= NULL
);
1209 /* If it's already in CLOSING, CLOSED or ERROR, this is a no-op */
1210 if (CHANNEL_CONDEMNED(chan
))
1213 log_debug(LD_CHANNEL
,
1214 "Closing channel %p (global ID " U64_FORMAT
") "
1215 "due to lower-layer event",
1216 chan
, U64_PRINTF_ARG(chan
->global_identifier
));
1218 /* Note closing by event from below */
1219 chan
->reason_for_closing
= CHANNEL_CLOSE_FROM_BELOW
;
1221 /* Change state to CLOSING */
1222 channel_change_state(chan
, CHANNEL_STATE_CLOSING
);
1226 * Close a channel listener from the lower layer
1228 * Notify the channel code that the channel listener is being closed due to a
1229 * non-error condition in the lower layer. This does not call the close()
1230 * method, since the lower layer already knows.
1234 channel_listener_close_from_lower_layer(channel_listener_t
*chan_l
)
1236 tor_assert(chan_l
!= NULL
);
1238 /* If it's already in CLOSING, CLOSED or ERROR, this is a no-op */
1239 if (chan_l
->state
== CHANNEL_LISTENER_STATE_CLOSING
||
1240 chan_l
->state
== CHANNEL_LISTENER_STATE_CLOSED
||
1241 chan_l
->state
== CHANNEL_LISTENER_STATE_ERROR
) return;
1243 log_debug(LD_CHANNEL
,
1244 "Closing channel listener %p (global ID " U64_FORMAT
") "
1245 "due to lower-layer event",
1246 chan_l
, U64_PRINTF_ARG(chan_l
->global_identifier
));
1248 /* Note closing by event from below */
1249 chan_l
->reason_for_closing
= CHANNEL_LISTENER_CLOSE_FROM_BELOW
;
1251 /* Change state to CLOSING */
1252 channel_listener_change_state(chan_l
, CHANNEL_LISTENER_STATE_CLOSING
);
1256 * Notify that the channel is being closed due to an error condition
1258 * This function is called by the lower layer implementing the transport
1259 * when a channel must be closed due to an error condition. This does not
1260 * call the channel's close method, since the lower layer already knows.
1264 channel_close_for_error(channel_t
*chan
)
1266 tor_assert(chan
!= NULL
);
1268 /* If it's already in CLOSING, CLOSED or ERROR, this is a no-op */
1269 if (CHANNEL_CONDEMNED(chan
))
1272 log_debug(LD_CHANNEL
,
1273 "Closing channel %p due to lower-layer error",
1276 /* Note closing by event from below */
1277 chan
->reason_for_closing
= CHANNEL_CLOSE_FOR_ERROR
;
1279 /* Change state to CLOSING */
1280 channel_change_state(chan
, CHANNEL_STATE_CLOSING
);
1284 * Notify that the channel listener is being closed due to an error condition
1286 * This function is called by the lower layer implementing the transport
1287 * when a channel listener must be closed due to an error condition. This
1288 * does not call the channel listener's close method, since the lower layer
1293 channel_listener_close_for_error(channel_listener_t
*chan_l
)
1295 tor_assert(chan_l
!= NULL
);
1297 /* If it's already in CLOSING, CLOSED or ERROR, this is a no-op */
1298 if (chan_l
->state
== CHANNEL_LISTENER_STATE_CLOSING
||
1299 chan_l
->state
== CHANNEL_LISTENER_STATE_CLOSED
||
1300 chan_l
->state
== CHANNEL_LISTENER_STATE_ERROR
) return;
1302 log_debug(LD_CHANNEL
,
1303 "Closing channel listener %p (global ID " U64_FORMAT
") "
1304 "due to lower-layer error",
1305 chan_l
, U64_PRINTF_ARG(chan_l
->global_identifier
));
1307 /* Note closing by event from below */
1308 chan_l
->reason_for_closing
= CHANNEL_LISTENER_CLOSE_FOR_ERROR
;
1310 /* Change state to CLOSING */
1311 channel_listener_change_state(chan_l
, CHANNEL_LISTENER_STATE_CLOSING
);
1315 * Notify that the lower layer is finished closing the channel
1317 * This function should be called by the lower layer when a channel
1318 * is finished closing and it should be regarded as inactive and
1319 * freed by the channel code.
1323 channel_closed(channel_t
*chan
)
1326 tor_assert(CHANNEL_CONDEMNED(chan
));
1328 /* No-op if already inactive */
1329 if (CHANNEL_FINISHED(chan
))
1332 /* Inform any pending (not attached) circs that they should
1334 if (! chan
->has_been_open
)
1335 circuit_n_chan_done(chan
, 0, 0);
1337 /* Now close all the attached circuits on it. */
1338 circuit_unlink_all_from_channel(chan
, END_CIRC_REASON_CHANNEL_CLOSED
);
1340 if (chan
->reason_for_closing
!= CHANNEL_CLOSE_FOR_ERROR
) {
1341 channel_change_state(chan
, CHANNEL_STATE_CLOSED
);
1343 channel_change_state(chan
, CHANNEL_STATE_ERROR
);
1348 * Notify that the lower layer is finished closing the channel listener
1350 * This function should be called by the lower layer when a channel listener
1351 * is finished closing and it should be regarded as inactive and
1352 * freed by the channel code.
1356 channel_listener_closed(channel_listener_t
*chan_l
)
1359 tor_assert(chan_l
->state
== CHANNEL_LISTENER_STATE_CLOSING
||
1360 chan_l
->state
== CHANNEL_LISTENER_STATE_CLOSED
||
1361 chan_l
->state
== CHANNEL_LISTENER_STATE_ERROR
);
1363 /* No-op if already inactive */
1364 if (chan_l
->state
== CHANNEL_LISTENER_STATE_CLOSED
||
1365 chan_l
->state
== CHANNEL_LISTENER_STATE_ERROR
) return;
1367 if (chan_l
->reason_for_closing
!= CHANNEL_LISTENER_CLOSE_FOR_ERROR
) {
1368 channel_listener_change_state(chan_l
, CHANNEL_LISTENER_STATE_CLOSED
);
1370 channel_listener_change_state(chan_l
, CHANNEL_LISTENER_STATE_ERROR
);
1375 * Clear the identity_digest of a channel
1377 * This function clears the identity digest of the remote endpoint for a
1378 * channel; this is intended for use by the lower layer.
1382 channel_clear_identity_digest(channel_t
*chan
)
1384 int state_not_in_map
;
1388 log_debug(LD_CHANNEL
,
1389 "Clearing remote endpoint digest on channel %p with "
1390 "global ID " U64_FORMAT
,
1391 chan
, U64_PRINTF_ARG(chan
->global_identifier
));
1393 state_not_in_map
= CHANNEL_CONDEMNED(chan
);
1395 if (!state_not_in_map
&& chan
->registered
&&
1396 !tor_digest_is_zero(chan
->identity_digest
))
1397 /* if it's registered get it out of the digest map */
1398 channel_remove_from_digest_map(chan
);
1400 memset(chan
->identity_digest
, 0,
1401 sizeof(chan
->identity_digest
));
1405 * Set the identity_digest of a channel
1407 * This function sets the identity digest of the remote endpoint for a
1408 * channel; this is intended for use by the lower layer.
1412 channel_set_identity_digest(channel_t
*chan
,
1413 const char *identity_digest
)
1415 int was_in_digest_map
, should_be_in_digest_map
, state_not_in_map
;
1419 log_debug(LD_CHANNEL
,
1420 "Setting remote endpoint digest on channel %p with "
1421 "global ID " U64_FORMAT
" to digest %s",
1422 chan
, U64_PRINTF_ARG(chan
->global_identifier
),
1424 hex_str(identity_digest
, DIGEST_LEN
) : "(null)");
1426 state_not_in_map
= CHANNEL_CONDEMNED(chan
);
1429 !state_not_in_map
&&
1431 !tor_digest_is_zero(chan
->identity_digest
);
1432 should_be_in_digest_map
=
1433 !state_not_in_map
&&
1436 !tor_digest_is_zero(identity_digest
));
1438 if (was_in_digest_map
)
1439 /* We should always remove it; we'll add it back if we're writing
1442 channel_remove_from_digest_map(chan
);
1444 if (identity_digest
) {
1445 memcpy(chan
->identity_digest
,
1447 sizeof(chan
->identity_digest
));
1449 memset(chan
->identity_digest
, 0,
1450 sizeof(chan
->identity_digest
));
1453 /* Put it in the digest map if we should */
1454 if (should_be_in_digest_map
)
1455 channel_add_to_digest_map(chan
);
1459 * Clear the remote end metadata (identity_digest/nickname) of a channel
1461 * This function clears all the remote end info from a channel; this is
1462 * intended for use by the lower layer.
1466 channel_clear_remote_end(channel_t
*chan
)
1468 int state_not_in_map
;
1472 log_debug(LD_CHANNEL
,
1473 "Clearing remote endpoint identity on channel %p with "
1474 "global ID " U64_FORMAT
,
1475 chan
, U64_PRINTF_ARG(chan
->global_identifier
));
1477 state_not_in_map
= CHANNEL_CONDEMNED(chan
);
1479 if (!state_not_in_map
&& chan
->registered
&&
1480 !tor_digest_is_zero(chan
->identity_digest
))
1481 /* if it's registered get it out of the digest map */
1482 channel_remove_from_digest_map(chan
);
1484 memset(chan
->identity_digest
, 0,
1485 sizeof(chan
->identity_digest
));
1486 tor_free(chan
->nickname
);
1490 * Set the remote end metadata (identity_digest/nickname) of a channel
1492 * This function sets new remote end info on a channel; this is intended
1493 * for use by the lower layer.
1497 channel_set_remote_end(channel_t
*chan
,
1498 const char *identity_digest
,
1499 const char *nickname
)
1501 int was_in_digest_map
, should_be_in_digest_map
, state_not_in_map
;
1505 log_debug(LD_CHANNEL
,
1506 "Setting remote endpoint identity on channel %p with "
1507 "global ID " U64_FORMAT
" to nickname %s, digest %s",
1508 chan
, U64_PRINTF_ARG(chan
->global_identifier
),
1509 nickname
? nickname
: "(null)",
1511 hex_str(identity_digest
, DIGEST_LEN
) : "(null)");
1513 state_not_in_map
= CHANNEL_CONDEMNED(chan
);
1516 !state_not_in_map
&&
1518 !tor_digest_is_zero(chan
->identity_digest
);
1519 should_be_in_digest_map
=
1520 !state_not_in_map
&&
1523 !tor_digest_is_zero(identity_digest
));
1525 if (was_in_digest_map
)
1526 /* We should always remove it; we'll add it back if we're writing
1529 channel_remove_from_digest_map(chan
);
1531 if (identity_digest
) {
1532 memcpy(chan
->identity_digest
,
1534 sizeof(chan
->identity_digest
));
1537 memset(chan
->identity_digest
, 0,
1538 sizeof(chan
->identity_digest
));
1541 tor_free(chan
->nickname
);
1543 chan
->nickname
= tor_strdup(nickname
);
1545 /* Put it in the digest map if we should */
1546 if (should_be_in_digest_map
)
1547 channel_add_to_digest_map(chan
);
1551 * Duplicate a cell queue entry; this is a shallow copy intended for use
1552 * in channel_write_cell_queue_entry().
1555 static cell_queue_entry_t
*
1556 cell_queue_entry_dup(cell_queue_entry_t
*q
)
1558 cell_queue_entry_t
*rv
= NULL
;
1562 rv
= tor_malloc(sizeof(*rv
));
1563 memcpy(rv
, q
, sizeof(*rv
));
1569 * Free a cell_queue_entry_t; the handed_off parameter indicates whether
1570 * the contents were passed to the lower layer (it is responsible for
1571 * them) or not (we should free).
1575 cell_queue_entry_free(cell_queue_entry_t
*q
, int handed_off
)
1581 * If we handed it off, the recipient becomes responsible (or
1582 * with packed cells the channel_t subclass calls packed_cell
1583 * free after writing out its contents; see, e.g.,
1584 * channel_tls_write_packed_cell_method(). Otherwise, we have
1585 * to take care of it here if possible.
1588 case CELL_QUEUE_FIXED
:
1589 if (q
->u
.fixed
.cell
) {
1591 * There doesn't seem to be a cell_free() function anywhere in the
1592 * pre-channel code; just use tor_free()
1594 tor_free(q
->u
.fixed
.cell
);
1597 case CELL_QUEUE_PACKED
:
1598 if (q
->u
.packed
.packed_cell
) {
1599 packed_cell_free(q
->u
.packed
.packed_cell
);
1602 case CELL_QUEUE_VAR
:
1603 if (q
->u
.var
.var_cell
) {
1605 * This one's in connection_or.c; it'd be nice to figure out the
1606 * whole flow of cells from one end to the other and factor the
1607 * cell memory management functions like this out of the specific
1610 var_cell_free(q
->u
.var
.var_cell
);
1615 * Nothing we can do if we don't know the type; this will
1616 * have been warned about elsewhere.
1626 * Check whether a cell queue entry is padding; this is a helper function
1627 * for channel_write_cell_queue_entry()
1631 cell_queue_entry_is_padding(cell_queue_entry_t
*q
)
1635 if (q
->type
== CELL_QUEUE_FIXED
) {
1636 if (q
->u
.fixed
.cell
) {
1637 if (q
->u
.fixed
.cell
->command
== CELL_PADDING
||
1638 q
->u
.fixed
.cell
->command
== CELL_VPADDING
) {
1642 } else if (q
->type
== CELL_QUEUE_VAR
) {
1643 if (q
->u
.var
.var_cell
) {
1644 if (q
->u
.var
.var_cell
->command
== CELL_PADDING
||
1645 q
->u
.var
.var_cell
->command
== CELL_VPADDING
) {
1656 * Allocate a new cell queue entry for a fixed-size cell
1659 static cell_queue_entry_t
*
1660 cell_queue_entry_new_fixed(cell_t
*cell
)
1662 cell_queue_entry_t
*q
= NULL
;
1666 q
= tor_malloc(sizeof(*q
));
1667 q
->type
= CELL_QUEUE_FIXED
;
1668 q
->u
.fixed
.cell
= cell
;
1674 * Allocate a new cell queue entry for a variable-size cell
1677 static cell_queue_entry_t
*
1678 cell_queue_entry_new_var(var_cell_t
*var_cell
)
1680 cell_queue_entry_t
*q
= NULL
;
1682 tor_assert(var_cell
);
1684 q
= tor_malloc(sizeof(*q
));
1685 q
->type
= CELL_QUEUE_VAR
;
1686 q
->u
.var
.var_cell
= var_cell
;
1692 * Ask how big the cell contained in a cell_queue_entry_t is
1696 channel_get_cell_queue_entry_size(channel_t
*chan
, cell_queue_entry_t
*q
)
1704 case CELL_QUEUE_FIXED
:
1705 rv
= get_cell_network_size(chan
->wide_circ_ids
);
1707 case CELL_QUEUE_VAR
:
1708 rv
= get_var_cell_header_size(chan
->wide_circ_ids
) +
1709 (q
->u
.var
.var_cell
? q
->u
.var
.var_cell
->payload_len
: 0);
1711 case CELL_QUEUE_PACKED
:
1712 rv
= get_cell_network_size(chan
->wide_circ_ids
);
1722 * Write to a channel based on a cell_queue_entry_t
1724 * Given a cell_queue_entry_t filled out by the caller, try to send the cell
1725 * and queue it if we can't.
1729 channel_write_cell_queue_entry(channel_t
*chan
, cell_queue_entry_t
*q
)
1731 int result
= 0, sent
= 0;
1732 cell_queue_entry_t
*tmp
= NULL
;
1738 /* Assert that the state makes sense for a cell write */
1739 tor_assert(CHANNEL_CAN_HANDLE_CELLS(chan
));
1743 if (is_destroy_cell(chan
, q
, &circ_id
)) {
1744 channel_note_destroy_not_pending(chan
, circ_id
);
1748 /* For statistical purposes, figure out how big this cell is */
1749 cell_bytes
= channel_get_cell_queue_entry_size(chan
, q
);
1751 /* Can we send it right out? If so, try */
1752 if (TOR_SIMPLEQ_EMPTY(&chan
->outgoing_queue
) &&
1753 CHANNEL_IS_OPEN(chan
)) {
1754 /* Pick the right write function for this cell type and save the result */
1756 case CELL_QUEUE_FIXED
:
1757 tor_assert(chan
->write_cell
);
1758 tor_assert(q
->u
.fixed
.cell
);
1759 result
= chan
->write_cell(chan
, q
->u
.fixed
.cell
);
1761 case CELL_QUEUE_PACKED
:
1762 tor_assert(chan
->write_packed_cell
);
1763 tor_assert(q
->u
.packed
.packed_cell
);
1764 result
= chan
->write_packed_cell(chan
, q
->u
.packed
.packed_cell
);
1766 case CELL_QUEUE_VAR
:
1767 tor_assert(chan
->write_var_cell
);
1768 tor_assert(q
->u
.var
.var_cell
);
1769 result
= chan
->write_var_cell(chan
, q
->u
.var
.var_cell
);
1775 /* Check if we got it out */
1778 /* Timestamp for transmission */
1779 channel_timestamp_xmit(chan
);
1780 /* If we're here the queue is empty, so it's drained too */
1781 channel_timestamp_drained(chan
);
1782 /* Update the counter */
1783 ++(chan
->n_cells_xmitted
);
1784 chan
->n_bytes_xmitted
+= cell_bytes
;
1785 /* Update global counters */
1786 ++n_channel_cells_queued
;
1787 ++n_channel_cells_passed_to_lower_layer
;
1788 n_channel_bytes_queued
+= cell_bytes
;
1789 n_channel_bytes_passed_to_lower_layer
+= cell_bytes
;
1790 channel_assert_counter_consistency();
1795 /* Not sent, queue it */
1797 * We have to copy the queue entry passed in, since the caller probably
1800 tmp
= cell_queue_entry_dup(q
);
1801 TOR_SIMPLEQ_INSERT_TAIL(&chan
->outgoing_queue
, tmp
, next
);
1802 /* Update global counters */
1803 ++n_channel_cells_queued
;
1804 ++n_channel_cells_in_queues
;
1805 n_channel_bytes_queued
+= cell_bytes
;
1806 n_channel_bytes_in_queues
+= cell_bytes
;
1807 channel_assert_counter_consistency();
1808 /* Update channel queue size */
1809 chan
->bytes_in_queue
+= cell_bytes
;
1810 /* Try to process the queue? */
1811 if (CHANNEL_IS_OPEN(chan
)) channel_flush_cells(chan
);
1816 * Write a cell to a channel
1818 * Write a fixed-length cell to a channel using the write_cell() method.
1819 * This is equivalent to the pre-channels connection_or_write_cell_to_buf();
1820 * it is called by the transport-independent code to deliver a cell to a
1821 * channel for transmission.
1825 channel_write_cell(channel_t
*chan
, cell_t
*cell
)
1827 cell_queue_entry_t q
;
1832 if (CHANNEL_IS_CLOSING(chan
)) {
1833 log_debug(LD_CHANNEL
, "Discarding cell_t %p on closing channel %p with "
1834 "global ID "U64_FORMAT
, cell
, chan
,
1835 U64_PRINTF_ARG(chan
->global_identifier
));
1840 log_debug(LD_CHANNEL
,
1841 "Writing cell_t %p to channel %p with global ID "
1843 cell
, chan
, U64_PRINTF_ARG(chan
->global_identifier
));
1845 q
.type
= CELL_QUEUE_FIXED
;
1846 q
.u
.fixed
.cell
= cell
;
1847 channel_write_cell_queue_entry(chan
, &q
);
1849 /* Update the queue size estimate */
1850 channel_update_xmit_queue_size(chan
);
1854 * Write a packed cell to a channel
1856 * Write a packed cell to a channel using the write_cell() method. This is
1857 * called by the transport-independent code to deliver a packed cell to a
1858 * channel for transmission.
1862 channel_write_packed_cell(channel_t
*chan
, packed_cell_t
*packed_cell
)
1864 cell_queue_entry_t q
;
1867 tor_assert(packed_cell
);
1869 if (CHANNEL_IS_CLOSING(chan
)) {
1870 log_debug(LD_CHANNEL
, "Discarding packed_cell_t %p on closing channel %p "
1871 "with global ID "U64_FORMAT
, packed_cell
, chan
,
1872 U64_PRINTF_ARG(chan
->global_identifier
));
1873 packed_cell_free(packed_cell
);
1877 log_debug(LD_CHANNEL
,
1878 "Writing packed_cell_t %p to channel %p with global ID "
1881 U64_PRINTF_ARG(chan
->global_identifier
));
1883 q
.type
= CELL_QUEUE_PACKED
;
1884 q
.u
.packed
.packed_cell
= packed_cell
;
1885 channel_write_cell_queue_entry(chan
, &q
);
1887 /* Update the queue size estimate */
1888 channel_update_xmit_queue_size(chan
);
1892 * Write a variable-length cell to a channel
1894 * Write a variable-length cell to a channel using the write_cell() method.
1895 * This is equivalent to the pre-channels
1896 * connection_or_write_var_cell_to_buf(); it's called by the transport-
1897 * independent code to deliver a var_cell to a channel for transmission.
1901 channel_write_var_cell(channel_t
*chan
, var_cell_t
*var_cell
)
1903 cell_queue_entry_t q
;
1906 tor_assert(var_cell
);
1908 if (CHANNEL_IS_CLOSING(chan
)) {
1909 log_debug(LD_CHANNEL
, "Discarding var_cell_t %p on closing channel %p "
1910 "with global ID "U64_FORMAT
, var_cell
, chan
,
1911 U64_PRINTF_ARG(chan
->global_identifier
));
1912 var_cell_free(var_cell
);
1916 log_debug(LD_CHANNEL
,
1917 "Writing var_cell_t %p to channel %p with global ID "
1920 U64_PRINTF_ARG(chan
->global_identifier
));
1922 q
.type
= CELL_QUEUE_VAR
;
1923 q
.u
.var
.var_cell
= var_cell
;
1924 channel_write_cell_queue_entry(chan
, &q
);
1926 /* Update the queue size estimate */
1927 channel_update_xmit_queue_size(chan
);
1931 * Change channel state
1933 * This internal and subclass use only function is used to change channel
1934 * state, performing all transition validity checks and whatever actions
1935 * are appropriate to the state transition in question.
1939 channel_change_state(channel_t
*chan
, channel_state_t to_state
)
1941 channel_state_t from_state
;
1942 unsigned char was_active
, is_active
;
1943 unsigned char was_in_id_map
, is_in_id_map
;
1946 from_state
= chan
->state
;
1948 tor_assert(channel_state_is_valid(from_state
));
1949 tor_assert(channel_state_is_valid(to_state
));
1950 tor_assert(channel_state_can_transition(chan
->state
, to_state
));
1952 /* Check for no-op transitions */
1953 if (from_state
== to_state
) {
1954 log_debug(LD_CHANNEL
,
1955 "Got no-op transition from \"%s\" to itself on channel %p"
1956 "(global ID " U64_FORMAT
")",
1957 channel_state_to_string(to_state
),
1958 chan
, U64_PRINTF_ARG(chan
->global_identifier
));
1962 /* If we're going to a closing or closed state, we must have a reason set */
1963 if (to_state
== CHANNEL_STATE_CLOSING
||
1964 to_state
== CHANNEL_STATE_CLOSED
||
1965 to_state
== CHANNEL_STATE_ERROR
) {
1966 tor_assert(chan
->reason_for_closing
!= CHANNEL_NOT_CLOSING
);
1970 * We need to maintain the queues here for some transitions:
1971 * when we enter CHANNEL_STATE_OPEN (especially from CHANNEL_STATE_MAINT)
1972 * we may have a backlog of cells to transmit, so drain the queues in
1973 * that case, and when going to CHANNEL_STATE_CLOSED the subclass
1974 * should have made sure to finish sending things (or gone to
1975 * CHANNEL_STATE_ERROR if not possible), so we assert for that here.
1978 log_debug(LD_CHANNEL
,
1979 "Changing state of channel %p (global ID " U64_FORMAT
1980 ") from \"%s\" to \"%s\"",
1982 U64_PRINTF_ARG(chan
->global_identifier
),
1983 channel_state_to_string(chan
->state
),
1984 channel_state_to_string(to_state
));
1986 chan
->state
= to_state
;
1988 /* Need to add to the right lists if the channel is registered */
1989 if (chan
->registered
) {
1990 was_active
= !(from_state
== CHANNEL_STATE_CLOSED
||
1991 from_state
== CHANNEL_STATE_ERROR
);
1992 is_active
= !(to_state
== CHANNEL_STATE_CLOSED
||
1993 to_state
== CHANNEL_STATE_ERROR
);
1995 /* Need to take off active list and put on finished list? */
1996 if (was_active
&& !is_active
) {
1997 if (active_channels
) smartlist_remove(active_channels
, chan
);
1998 if (!finished_channels
) finished_channels
= smartlist_new();
1999 smartlist_add(finished_channels
, chan
);
2001 /* Need to put on active list? */
2002 else if (!was_active
&& is_active
) {
2003 if (finished_channels
) smartlist_remove(finished_channels
, chan
);
2004 if (!active_channels
) active_channels
= smartlist_new();
2005 smartlist_add(active_channels
, chan
);
2008 if (!tor_digest_is_zero(chan
->identity_digest
)) {
2009 /* Now we need to handle the identity map */
2010 was_in_id_map
= !(from_state
== CHANNEL_STATE_CLOSING
||
2011 from_state
== CHANNEL_STATE_CLOSED
||
2012 from_state
== CHANNEL_STATE_ERROR
);
2013 is_in_id_map
= !(to_state
== CHANNEL_STATE_CLOSING
||
2014 to_state
== CHANNEL_STATE_CLOSED
||
2015 to_state
== CHANNEL_STATE_ERROR
);
2017 if (!was_in_id_map
&& is_in_id_map
) channel_add_to_digest_map(chan
);
2018 else if (was_in_id_map
&& !is_in_id_map
)
2019 channel_remove_from_digest_map(chan
);
2024 * If we're going to a closed/closing state, we don't need scheduling any
2025 * more; in CHANNEL_STATE_MAINT we can't accept writes.
2027 if (to_state
== CHANNEL_STATE_CLOSING
||
2028 to_state
== CHANNEL_STATE_CLOSED
||
2029 to_state
== CHANNEL_STATE_ERROR
) {
2030 scheduler_release_channel(chan
);
2031 } else if (to_state
== CHANNEL_STATE_MAINT
) {
2032 scheduler_channel_doesnt_want_writes(chan
);
2036 * If we're closing, this channel no longer counts toward the global
2037 * estimated queue size; if we're open, it now does.
2039 if ((to_state
== CHANNEL_STATE_CLOSING
||
2040 to_state
== CHANNEL_STATE_CLOSED
||
2041 to_state
== CHANNEL_STATE_ERROR
) &&
2042 (from_state
== CHANNEL_STATE_OPEN
||
2043 from_state
== CHANNEL_STATE_MAINT
)) {
2044 estimated_total_queue_size
-= chan
->bytes_in_queue
;
2048 * If we're opening, this channel now does count toward the global
2049 * estimated queue size.
2051 if ((to_state
== CHANNEL_STATE_OPEN
||
2052 to_state
== CHANNEL_STATE_MAINT
) &&
2053 !(from_state
== CHANNEL_STATE_OPEN
||
2054 from_state
== CHANNEL_STATE_MAINT
)) {
2055 estimated_total_queue_size
+= chan
->bytes_in_queue
;
2058 /* Tell circuits if we opened and stuff */
2059 if (to_state
== CHANNEL_STATE_OPEN
) {
2060 channel_do_open_actions(chan
);
2061 chan
->has_been_open
= 1;
2063 /* Check for queued cells to process */
2064 if (! TOR_SIMPLEQ_EMPTY(&chan
->incoming_queue
))
2065 channel_process_cells(chan
);
2066 if (! TOR_SIMPLEQ_EMPTY(&chan
->outgoing_queue
))
2067 channel_flush_cells(chan
);
2068 } else if (to_state
== CHANNEL_STATE_CLOSED
||
2069 to_state
== CHANNEL_STATE_ERROR
) {
2070 /* Assert that all queues are empty */
2071 tor_assert(TOR_SIMPLEQ_EMPTY(&chan
->incoming_queue
));
2072 tor_assert(TOR_SIMPLEQ_EMPTY(&chan
->outgoing_queue
));
2077 * Change channel listener state
2079 * This internal and subclass use only function is used to change channel
2080 * listener state, performing all transition validity checks and whatever
2081 * actions are appropriate to the state transition in question.
2085 channel_listener_change_state(channel_listener_t
*chan_l
,
2086 channel_listener_state_t to_state
)
2088 channel_listener_state_t from_state
;
2089 unsigned char was_active
, is_active
;
2092 from_state
= chan_l
->state
;
2094 tor_assert(channel_listener_state_is_valid(from_state
));
2095 tor_assert(channel_listener_state_is_valid(to_state
));
2096 tor_assert(channel_listener_state_can_transition(chan_l
->state
, to_state
));
2098 /* Check for no-op transitions */
2099 if (from_state
== to_state
) {
2100 log_debug(LD_CHANNEL
,
2101 "Got no-op transition from \"%s\" to itself on channel "
2102 "listener %p (global ID " U64_FORMAT
")",
2103 channel_listener_state_to_string(to_state
),
2104 chan_l
, U64_PRINTF_ARG(chan_l
->global_identifier
));
2108 /* If we're going to a closing or closed state, we must have a reason set */
2109 if (to_state
== CHANNEL_LISTENER_STATE_CLOSING
||
2110 to_state
== CHANNEL_LISTENER_STATE_CLOSED
||
2111 to_state
== CHANNEL_LISTENER_STATE_ERROR
) {
2112 tor_assert(chan_l
->reason_for_closing
!= CHANNEL_LISTENER_NOT_CLOSING
);
2116 * We need to maintain the queues here for some transitions:
2117 * when we enter CHANNEL_STATE_OPEN (especially from CHANNEL_STATE_MAINT)
2118 * we may have a backlog of cells to transmit, so drain the queues in
2119 * that case, and when going to CHANNEL_STATE_CLOSED the subclass
2120 * should have made sure to finish sending things (or gone to
2121 * CHANNEL_STATE_ERROR if not possible), so we assert for that here.
2124 log_debug(LD_CHANNEL
,
2125 "Changing state of channel listener %p (global ID " U64_FORMAT
2126 "from \"%s\" to \"%s\"",
2127 chan_l
, U64_PRINTF_ARG(chan_l
->global_identifier
),
2128 channel_listener_state_to_string(chan_l
->state
),
2129 channel_listener_state_to_string(to_state
));
2131 chan_l
->state
= to_state
;
2133 /* Need to add to the right lists if the channel listener is registered */
2134 if (chan_l
->registered
) {
2135 was_active
= !(from_state
== CHANNEL_LISTENER_STATE_CLOSED
||
2136 from_state
== CHANNEL_LISTENER_STATE_ERROR
);
2137 is_active
= !(to_state
== CHANNEL_LISTENER_STATE_CLOSED
||
2138 to_state
== CHANNEL_LISTENER_STATE_ERROR
);
2140 /* Need to take off active list and put on finished list? */
2141 if (was_active
&& !is_active
) {
2142 if (active_listeners
) smartlist_remove(active_listeners
, chan_l
);
2143 if (!finished_listeners
) finished_listeners
= smartlist_new();
2144 smartlist_add(finished_listeners
, chan_l
);
2146 /* Need to put on active list? */
2147 else if (!was_active
&& is_active
) {
2148 if (finished_listeners
) smartlist_remove(finished_listeners
, chan_l
);
2149 if (!active_listeners
) active_listeners
= smartlist_new();
2150 smartlist_add(active_listeners
, chan_l
);
2154 if (to_state
== CHANNEL_LISTENER_STATE_CLOSED
||
2155 to_state
== CHANNEL_LISTENER_STATE_ERROR
) {
2156 /* Assert that the queue is empty */
2157 tor_assert(!(chan_l
->incoming_list
) ||
2158 smartlist_len(chan_l
->incoming_list
) == 0);
2163 * Try to flush cells to the lower layer
2165 * this is called by the lower layer to indicate that it wants more cells;
2166 * it will try to write up to num_cells cells from the channel's cell queue or
2167 * from circuits active on that channel, or as many as it has available if
2171 #define MAX_CELLS_TO_GET_FROM_CIRCUITS_FOR_UNLIMITED 256
2174 channel_flush_some_cells
, (channel_t
*chan
, ssize_t num_cells
))
2176 unsigned int unlimited
= 0;
2177 ssize_t flushed
= 0;
2178 int num_cells_from_circs
, clamped_num_cells
;
2179 int q_len_before
, q_len_after
;
2183 if (num_cells
< 0) unlimited
= 1;
2184 if (!unlimited
&& num_cells
<= flushed
) goto done
;
2186 /* If we aren't in CHANNEL_STATE_OPEN, nothing goes through */
2187 if (CHANNEL_IS_OPEN(chan
)) {
2188 /* Try to flush as much as we can that's already queued */
2189 flushed
+= channel_flush_some_cells_from_outgoing_queue(chan
,
2190 (unlimited
? -1 : num_cells
- flushed
));
2191 if (!unlimited
&& num_cells
<= flushed
) goto done
;
2193 if (circuitmux_num_cells(chan
->cmux
) > 0) {
2194 /* Calculate number of cells, including clamp */
2196 clamped_num_cells
= MAX_CELLS_TO_GET_FROM_CIRCUITS_FOR_UNLIMITED
;
2198 if (num_cells
- flushed
>
2199 MAX_CELLS_TO_GET_FROM_CIRCUITS_FOR_UNLIMITED
) {
2200 clamped_num_cells
= MAX_CELLS_TO_GET_FROM_CIRCUITS_FOR_UNLIMITED
;
2202 clamped_num_cells
= (int)(num_cells
- flushed
);
2207 * Keep track of the change in queue size; we have to count cells
2208 * channel_flush_from_first_active_circuit() writes out directly,
2209 * but not double-count ones we might get later in
2210 * channel_flush_some_cells_from_outgoing_queue()
2212 q_len_before
= chan_cell_queue_len(&(chan
->outgoing_queue
));
2214 /* Try to get more cells from any active circuits */
2215 num_cells_from_circs
= channel_flush_from_first_active_circuit(
2216 chan
, clamped_num_cells
);
2218 q_len_after
= chan_cell_queue_len(&(chan
->outgoing_queue
));
2221 * If it claims we got some, adjust the flushed counter and consider
2222 * processing the queue again
2224 if (num_cells_from_circs
> 0) {
2226 * Adjust flushed by the number of cells counted in
2227 * num_cells_from_circs that didn't go to the cell queue.
2230 if (q_len_after
> q_len_before
) {
2231 num_cells_from_circs
-= (q_len_after
- q_len_before
);
2232 if (num_cells_from_circs
< 0) num_cells_from_circs
= 0;
2235 flushed
+= num_cells_from_circs
;
2237 /* Now process the queue if necessary */
2239 if ((q_len_after
> q_len_before
) &&
2240 (unlimited
|| (flushed
< num_cells
))) {
2241 flushed
+= channel_flush_some_cells_from_outgoing_queue(chan
,
2242 (unlimited
? -1 : num_cells
- flushed
));
2253 * Flush cells from just the channel's outgoing cell queue
2255 * This gets called from channel_flush_some_cells() above to flush cells
2256 * just from the queue without trying for active_circuits.
2260 channel_flush_some_cells_from_outgoing_queue(channel_t
*chan
,
2263 unsigned int unlimited
= 0;
2264 ssize_t flushed
= 0;
2265 cell_queue_entry_t
*q
= NULL
;
2267 int free_q
= 0, handed_off
= 0;
2270 tor_assert(chan
->write_cell
);
2271 tor_assert(chan
->write_packed_cell
);
2272 tor_assert(chan
->write_var_cell
);
2274 if (num_cells
< 0) unlimited
= 1;
2275 if (!unlimited
&& num_cells
<= flushed
) return 0;
2277 /* If we aren't in CHANNEL_STATE_OPEN, nothing goes through */
2278 if (CHANNEL_IS_OPEN(chan
)) {
2279 while ((unlimited
|| num_cells
> flushed
) &&
2280 NULL
!= (q
= TOR_SIMPLEQ_FIRST(&chan
->outgoing_queue
))) {
2285 /* Figure out how big it is for statistical purposes */
2286 cell_size
= channel_get_cell_queue_entry_size(chan
, q
);
2288 * Okay, we have a good queue entry, try to give it to the lower
2292 case CELL_QUEUE_FIXED
:
2293 if (q
->u
.fixed
.cell
) {
2294 if (chan
->write_cell(chan
,
2297 channel_timestamp_xmit(chan
);
2298 ++(chan
->n_cells_xmitted
);
2299 chan
->n_bytes_xmitted
+= cell_size
;
2303 /* Else couldn't write it; leave it on the queue */
2305 /* This shouldn't happen */
2306 log_info(LD_CHANNEL
,
2307 "Saw broken cell queue entry of type CELL_QUEUE_FIXED "
2308 "with no cell on channel %p "
2309 "(global ID " U64_FORMAT
").",
2310 chan
, U64_PRINTF_ARG(chan
->global_identifier
));
2316 case CELL_QUEUE_PACKED
:
2317 if (q
->u
.packed
.packed_cell
) {
2318 if (chan
->write_packed_cell(chan
,
2319 q
->u
.packed
.packed_cell
)) {
2321 channel_timestamp_xmit(chan
);
2322 ++(chan
->n_cells_xmitted
);
2323 chan
->n_bytes_xmitted
+= cell_size
;
2327 /* Else couldn't write it; leave it on the queue */
2329 /* This shouldn't happen */
2330 log_info(LD_CHANNEL
,
2331 "Saw broken cell queue entry of type CELL_QUEUE_PACKED "
2332 "with no cell on channel %p "
2333 "(global ID " U64_FORMAT
").",
2334 chan
, U64_PRINTF_ARG(chan
->global_identifier
));
2340 case CELL_QUEUE_VAR
:
2341 if (q
->u
.var
.var_cell
) {
2342 if (chan
->write_var_cell(chan
,
2343 q
->u
.var
.var_cell
)) {
2345 channel_timestamp_xmit(chan
);
2346 ++(chan
->n_cells_xmitted
);
2347 chan
->n_bytes_xmitted
+= cell_size
;
2351 /* Else couldn't write it; leave it on the queue */
2353 /* This shouldn't happen */
2354 log_info(LD_CHANNEL
,
2355 "Saw broken cell queue entry of type CELL_QUEUE_VAR "
2356 "with no cell on channel %p "
2357 "(global ID " U64_FORMAT
").",
2358 chan
, U64_PRINTF_ARG(chan
->global_identifier
));
2365 /* Unknown type, log and free it */
2366 log_info(LD_CHANNEL
,
2367 "Saw an unknown cell queue entry type %d on channel %p "
2368 "(global ID " U64_FORMAT
"; ignoring it."
2369 " Someone should fix this.",
2370 q
->type
, chan
, U64_PRINTF_ARG(chan
->global_identifier
));
2376 * if free_q is set, we used it and should remove the queue entry;
2377 * we have to do the free down here so TOR_SIMPLEQ_REMOVE_HEAD isn't
2378 * accessing freed memory
2381 TOR_SIMPLEQ_REMOVE_HEAD(&chan
->outgoing_queue
, next
);
2383 * ...and we handed a cell off to the lower layer, so we should
2384 * update the counters.
2386 ++n_channel_cells_passed_to_lower_layer
;
2387 --n_channel_cells_in_queues
;
2388 n_channel_bytes_passed_to_lower_layer
+= cell_size
;
2389 n_channel_bytes_in_queues
-= cell_size
;
2390 channel_assert_counter_consistency();
2391 /* Update the channel's queue size too */
2392 chan
->bytes_in_queue
-= cell_size
;
2393 /* Finally, free q */
2394 cell_queue_entry_free(q
, handed_off
);
2397 /* No cell removed from list, so we can't go on any further */
2403 /* Did we drain the queue? */
2404 if (TOR_SIMPLEQ_EMPTY(&chan
->outgoing_queue
)) {
2405 channel_timestamp_drained(chan
);
2408 /* Update the estimate queue size */
2409 channel_update_xmit_queue_size(chan
);
2415 * Flush as many cells as we possibly can from the queue
2417 * This tries to flush as many cells from the queue as the lower layer
2418 * will take. It just calls channel_flush_some_cells_from_outgoing_queue()
2419 * in unlimited mode.
2423 channel_flush_cells(channel_t
*chan
)
2425 channel_flush_some_cells_from_outgoing_queue(chan
, -1);
2429 * Check if any cells are available
2431 * This gets used from the lower layer to check if any more cells are
2436 channel_more_to_flush(channel_t
*chan
)
2440 /* Check if we have any queued */
2441 if (! TOR_SIMPLEQ_EMPTY(&chan
->incoming_queue
))
2444 /* Check if any circuits would like to queue some */
2445 if (circuitmux_num_cells(chan
->cmux
) > 0) return 1;
2452 * Notify the channel we're done flushing the output in the lower layer
2454 * Connection.c will call this when we've flushed the output; there's some
2455 * dirreq-related maintenance to do.
2459 channel_notify_flushed(channel_t
*chan
)
2463 if (chan
->dirreq_id
!= 0)
2464 geoip_change_dirreq_state(chan
->dirreq_id
,
2466 DIRREQ_CHANNEL_BUFFER_FLUSHED
);
2470 * Process the queue of incoming channels on a listener
2472 * Use a listener's registered callback to process as many entries in the
2473 * queue of incoming channels as possible.
2477 channel_listener_process_incoming(channel_listener_t
*listener
)
2479 tor_assert(listener
);
2482 * CHANNEL_LISTENER_STATE_CLOSING permitted because we drain the queue
2483 * while closing a listener.
2485 tor_assert(listener
->state
== CHANNEL_LISTENER_STATE_LISTENING
||
2486 listener
->state
== CHANNEL_LISTENER_STATE_CLOSING
);
2487 tor_assert(listener
->listener
);
2489 log_debug(LD_CHANNEL
,
2490 "Processing queue of incoming connections for channel "
2491 "listener %p (global ID " U64_FORMAT
")",
2492 listener
, U64_PRINTF_ARG(listener
->global_identifier
));
2494 if (!(listener
->incoming_list
)) return;
2496 SMARTLIST_FOREACH_BEGIN(listener
->incoming_list
,
2497 channel_t
*, chan
) {
2500 log_debug(LD_CHANNEL
,
2501 "Handling incoming channel %p (" U64_FORMAT
") "
2502 "for listener %p (" U64_FORMAT
")",
2504 U64_PRINTF_ARG(chan
->global_identifier
),
2506 U64_PRINTF_ARG(listener
->global_identifier
));
2507 /* Make sure this is set correctly */
2508 channel_mark_incoming(chan
);
2509 listener
->listener(listener
, chan
);
2510 } SMARTLIST_FOREACH_END(chan
);
2512 smartlist_free(listener
->incoming_list
);
2513 listener
->incoming_list
= NULL
;
2517 * Take actions required when a channel becomes open
2519 * Handle actions we should do when we know a channel is open; a lot of
2520 * this comes from the old connection_or_set_state_open() of connection_or.c.
2522 * Because of this mechanism, future channel_t subclasses should take care
2523 * not to change a channel to from CHANNEL_STATE_OPENING to CHANNEL_STATE_OPEN
2524 * until there is positive confirmation that the network is operational.
2525 * In particular, anything UDP-based should not make this transition until a
2526 * packet is received from the other side.
2530 channel_do_open_actions(channel_t
*chan
)
2532 tor_addr_t remote_addr
;
2534 time_t now
= time(NULL
);
2535 int close_origin_circuits
= 0;
2539 started_here
= channel_is_outgoing(chan
);
2542 circuit_build_times_network_is_live(get_circuit_build_times_mutable());
2543 rep_hist_note_connect_succeeded(chan
->identity_digest
, now
);
2544 if (entry_guard_register_connect_status(
2545 chan
->identity_digest
, 1, 0, now
) < 0) {
2546 /* Close any circuits pending on this channel. We leave it in state
2547 * 'open' though, because it didn't actually *fail* -- we just
2548 * chose not to use it. */
2550 "New entry guard was reachable, but closing this "
2551 "connection so we can retry the earlier entry guards.");
2552 close_origin_circuits
= 1;
2554 router_set_status(chan
->identity_digest
, 1);
2556 /* only report it to the geoip module if it's not a known router */
2557 if (!router_get_by_id_digest(chan
->identity_digest
)) {
2558 if (channel_get_addr_if_possible(chan
, &remote_addr
)) {
2559 char *transport_name
= NULL
;
2560 if (chan
->get_transport_name(chan
, &transport_name
) < 0)
2561 transport_name
= NULL
;
2563 geoip_note_client_seen(GEOIP_CLIENT_CONNECT
,
2564 &remote_addr
, transport_name
,
2566 tor_free(transport_name
);
2568 /* Otherwise the underlying transport can't tell us this, so skip it */
2572 circuit_n_chan_done(chan
, 1, close_origin_circuits
);
2576 * Queue an incoming channel on a listener
2578 * Internal and subclass use only function to queue an incoming channel from
2579 * a listener. A subclass of channel_listener_t should call this when a new
2580 * incoming channel is created.
2584 channel_listener_queue_incoming(channel_listener_t
*listener
,
2585 channel_t
*incoming
)
2587 int need_to_queue
= 0;
2589 tor_assert(listener
);
2590 tor_assert(listener
->state
== CHANNEL_LISTENER_STATE_LISTENING
);
2591 tor_assert(incoming
);
2593 log_debug(LD_CHANNEL
,
2594 "Queueing incoming channel %p (global ID " U64_FORMAT
") on "
2595 "channel listener %p (global ID " U64_FORMAT
")",
2596 incoming
, U64_PRINTF_ARG(incoming
->global_identifier
),
2597 listener
, U64_PRINTF_ARG(listener
->global_identifier
));
2599 /* Do we need to queue it, or can we just call the listener right away? */
2600 if (!(listener
->listener
)) need_to_queue
= 1;
2601 if (listener
->incoming_list
&&
2602 (smartlist_len(listener
->incoming_list
) > 0))
2605 /* If we need to queue and have no queue, create one */
2606 if (need_to_queue
&& !(listener
->incoming_list
)) {
2607 listener
->incoming_list
= smartlist_new();
2610 /* Bump the counter and timestamp it */
2611 channel_listener_timestamp_active(listener
);
2612 channel_listener_timestamp_accepted(listener
);
2613 ++(listener
->n_accepted
);
2615 /* If we don't need to queue, process it right away */
2616 if (!need_to_queue
) {
2617 tor_assert(listener
->listener
);
2618 listener
->listener(listener
, incoming
);
2621 * Otherwise, we need to queue; queue and then process the queue if
2625 tor_assert(listener
->incoming_list
);
2626 smartlist_add(listener
->incoming_list
, incoming
);
2627 if (listener
->listener
) channel_listener_process_incoming(listener
);
2632 * Process queued incoming cells
2634 * Process as many queued cells as we can from the incoming
2639 channel_process_cells(channel_t
*chan
)
2641 cell_queue_entry_t
*q
;
2643 tor_assert(CHANNEL_IS_CLOSING(chan
) || CHANNEL_IS_MAINT(chan
) ||
2644 CHANNEL_IS_OPEN(chan
));
2646 log_debug(LD_CHANNEL
,
2647 "Processing as many incoming cells as we can for channel %p",
2650 /* Nothing we can do if we have no registered cell handlers */
2651 if (!(chan
->cell_handler
||
2652 chan
->var_cell_handler
)) return;
2653 /* Nothing we can do if we have no cells */
2654 if (TOR_SIMPLEQ_EMPTY(&chan
->incoming_queue
)) return;
2657 * Process cells until we're done or find one we have no current handler
2660 * We must free the cells here after calling the handler, since custody
2661 * of the buffer was given to the channel layer when they were queued;
2662 * see comments on memory management in channel_queue_cell() and in
2663 * channel_queue_var_cell() below.
2665 while (NULL
!= (q
= TOR_SIMPLEQ_FIRST(&chan
->incoming_queue
))) {
2667 tor_assert(q
->type
== CELL_QUEUE_FIXED
||
2668 q
->type
== CELL_QUEUE_VAR
);
2670 if (q
->type
== CELL_QUEUE_FIXED
&&
2671 chan
->cell_handler
) {
2672 /* Handle a fixed-length cell */
2673 TOR_SIMPLEQ_REMOVE_HEAD(&chan
->incoming_queue
, next
);
2674 tor_assert(q
->u
.fixed
.cell
);
2675 log_debug(LD_CHANNEL
,
2676 "Processing incoming cell_t %p for channel %p (global ID "
2678 q
->u
.fixed
.cell
, chan
,
2679 U64_PRINTF_ARG(chan
->global_identifier
));
2680 chan
->cell_handler(chan
, q
->u
.fixed
.cell
);
2681 tor_free(q
->u
.fixed
.cell
);
2683 } else if (q
->type
== CELL_QUEUE_VAR
&&
2684 chan
->var_cell_handler
) {
2685 /* Handle a variable-length cell */
2686 TOR_SIMPLEQ_REMOVE_HEAD(&chan
->incoming_queue
, next
);
2687 tor_assert(q
->u
.var
.var_cell
);
2688 log_debug(LD_CHANNEL
,
2689 "Processing incoming var_cell_t %p for channel %p (global ID "
2691 q
->u
.var
.var_cell
, chan
,
2692 U64_PRINTF_ARG(chan
->global_identifier
));
2693 chan
->var_cell_handler(chan
, q
->u
.var
.var_cell
);
2694 tor_free(q
->u
.var
.var_cell
);
2697 /* Can't handle this one */
2704 * Queue incoming cell
2706 * This should be called by a channel_t subclass to queue an incoming fixed-
2707 * length cell for processing, and process it if possible.
2711 channel_queue_cell(channel_t
*chan
, cell_t
*cell
)
2713 int need_to_queue
= 0;
2714 cell_queue_entry_t
*q
;
2715 cell_t
*cell_copy
= NULL
;
2719 tor_assert(CHANNEL_IS_OPEN(chan
));
2721 /* Do we need to queue it, or can we just call the handler right away? */
2722 if (!(chan
->cell_handler
)) need_to_queue
= 1;
2723 if (! TOR_SIMPLEQ_EMPTY(&chan
->incoming_queue
))
2726 /* Timestamp for receiving */
2727 channel_timestamp_recv(chan
);
2729 /* Update the counters */
2730 ++(chan
->n_cells_recved
);
2731 chan
->n_bytes_recved
+= get_cell_network_size(chan
->wide_circ_ids
);
2733 /* If we don't need to queue we can just call cell_handler */
2734 if (!need_to_queue
) {
2735 tor_assert(chan
->cell_handler
);
2736 log_debug(LD_CHANNEL
,
2737 "Directly handling incoming cell_t %p for channel %p "
2738 "(global ID " U64_FORMAT
")",
2740 U64_PRINTF_ARG(chan
->global_identifier
));
2741 chan
->cell_handler(chan
, cell
);
2744 * Otherwise queue it and then process the queue if possible.
2746 * We queue a copy, not the original pointer - it might have been on the
2747 * stack in connection_or_process_cells_from_inbuf() (or another caller
2748 * if we ever have a subclass other than channel_tls_t), or be freed
2749 * there after we return. This is the uncommon case; the non-copying
2750 * fast path occurs in the if (!need_to_queue) case above when the
2751 * upper layer has installed cell handlers.
2753 cell_copy
= tor_malloc_zero(sizeof(cell_t
));
2754 memcpy(cell_copy
, cell
, sizeof(cell_t
));
2755 q
= cell_queue_entry_new_fixed(cell_copy
);
2756 log_debug(LD_CHANNEL
,
2757 "Queueing incoming cell_t %p for channel %p "
2758 "(global ID " U64_FORMAT
")",
2760 U64_PRINTF_ARG(chan
->global_identifier
));
2761 TOR_SIMPLEQ_INSERT_TAIL(&chan
->incoming_queue
, q
, next
);
2762 if (chan
->cell_handler
||
2763 chan
->var_cell_handler
) {
2764 channel_process_cells(chan
);
2770 * Queue incoming variable-length cell
2772 * This should be called by a channel_t subclass to queue an incoming
2773 * variable-length cell for processing, and process it if possible.
2777 channel_queue_var_cell(channel_t
*chan
, var_cell_t
*var_cell
)
2779 int need_to_queue
= 0;
2780 cell_queue_entry_t
*q
;
2781 var_cell_t
*cell_copy
= NULL
;
2784 tor_assert(var_cell
);
2785 tor_assert(CHANNEL_IS_OPEN(chan
));
2787 /* Do we need to queue it, or can we just call the handler right away? */
2788 if (!(chan
->var_cell_handler
)) need_to_queue
= 1;
2789 if (! TOR_SIMPLEQ_EMPTY(&chan
->incoming_queue
))
2792 /* Timestamp for receiving */
2793 channel_timestamp_recv(chan
);
2795 /* Update the counter */
2796 ++(chan
->n_cells_recved
);
2797 chan
->n_bytes_recved
+= get_var_cell_header_size(chan
->wide_circ_ids
) +
2798 var_cell
->payload_len
;
2800 /* If we don't need to queue we can just call cell_handler */
2801 if (!need_to_queue
) {
2802 tor_assert(chan
->var_cell_handler
);
2803 log_debug(LD_CHANNEL
,
2804 "Directly handling incoming var_cell_t %p for channel %p "
2805 "(global ID " U64_FORMAT
")",
2807 U64_PRINTF_ARG(chan
->global_identifier
));
2808 chan
->var_cell_handler(chan
, var_cell
);
2811 * Otherwise queue it and then process the queue if possible.
2813 * We queue a copy, not the original pointer - it might have been on the
2814 * stack in connection_or_process_cells_from_inbuf() (or another caller
2815 * if we ever have a subclass other than channel_tls_t), or be freed
2816 * there after we return. This is the uncommon case; the non-copying
2817 * fast path occurs in the if (!need_to_queue) case above when the
2818 * upper layer has installed cell handlers.
2820 cell_copy
= var_cell_copy(var_cell
);
2821 q
= cell_queue_entry_new_var(cell_copy
);
2822 log_debug(LD_CHANNEL
,
2823 "Queueing incoming var_cell_t %p for channel %p "
2824 "(global ID " U64_FORMAT
")",
2826 U64_PRINTF_ARG(chan
->global_identifier
));
2827 TOR_SIMPLEQ_INSERT_TAIL(&chan
->incoming_queue
, q
, next
);
2828 if (chan
->cell_handler
||
2829 chan
->var_cell_handler
) {
2830 channel_process_cells(chan
);
2835 /** If <b>packed_cell</b> on <b>chan</b> is a destroy cell, then set
2836 * *<b>circid_out</b> to its circuit ID, and return true. Otherwise, return
2838 /* XXXX Move this function. */
2840 packed_cell_is_destroy(channel_t
*chan
,
2841 const packed_cell_t
*packed_cell
,
2842 circid_t
*circid_out
)
2844 if (chan
->wide_circ_ids
) {
2845 if (packed_cell
->body
[4] == CELL_DESTROY
) {
2846 *circid_out
= ntohl(get_uint32(packed_cell
->body
));
2850 if (packed_cell
->body
[2] == CELL_DESTROY
) {
2851 *circid_out
= ntohs(get_uint16(packed_cell
->body
));
2859 * Assert that the global channel stats counters are internally consistent
2863 channel_assert_counter_consistency(void)
2865 tor_assert(n_channel_cells_queued
==
2866 (n_channel_cells_in_queues
+ n_channel_cells_passed_to_lower_layer
));
2867 tor_assert(n_channel_bytes_queued
==
2868 (n_channel_bytes_in_queues
+ n_channel_bytes_passed_to_lower_layer
));
2873 is_destroy_cell(channel_t
*chan
,
2874 const cell_queue_entry_t
*q
, circid_t
*circid_out
)
2878 case CELL_QUEUE_FIXED
:
2879 if (q
->u
.fixed
.cell
->command
== CELL_DESTROY
) {
2880 *circid_out
= q
->u
.fixed
.cell
->circ_id
;
2884 case CELL_QUEUE_VAR
:
2885 if (q
->u
.var
.var_cell
->command
== CELL_DESTROY
) {
2886 *circid_out
= q
->u
.var
.var_cell
->circ_id
;
2890 case CELL_QUEUE_PACKED
:
2891 return packed_cell_is_destroy(chan
, q
->u
.packed
.packed_cell
, circid_out
);
2897 * Send destroy cell on a channel
2899 * Write a destroy cell with circ ID <b>circ_id</b> and reason <b>reason</b>
2900 * onto channel <b>chan</b>. Don't perform range-checking on reason:
2901 * we may want to propagate reasons from other cells.
2905 channel_send_destroy(circid_t circ_id
, channel_t
*chan
, int reason
)
2909 log_warn(LD_BUG
, "Attempted to send a destroy cell for circID 0 "
2910 "on a channel " U64_FORMAT
" at %p in state %s (%d)",
2911 U64_PRINTF_ARG(chan
->global_identifier
),
2912 chan
, channel_state_to_string(chan
->state
),
2917 /* Check to make sure we can send on this channel first */
2918 if (!CHANNEL_CONDEMNED(chan
) && chan
->cmux
) {
2919 channel_note_destroy_pending(chan
, circ_id
);
2920 circuitmux_append_destroy_cell(chan
, chan
->cmux
, circ_id
, reason
);
2922 "Sending destroy (circID %u) on channel %p "
2923 "(global ID " U64_FORMAT
")",
2924 (unsigned)circ_id
, chan
,
2925 U64_PRINTF_ARG(chan
->global_identifier
));
2928 "Someone called channel_send_destroy() for circID %u "
2929 "on a channel " U64_FORMAT
" at %p in state %s (%d)",
2930 (unsigned)circ_id
, U64_PRINTF_ARG(chan
->global_identifier
),
2931 chan
, channel_state_to_string(chan
->state
),
2939 * Dump channel statistics to the log
2941 * This is called from dumpstats() in main.c and spams the log with
2942 * statistics on channels.
2946 channel_dumpstats(int severity
)
2948 if (all_channels
&& smartlist_len(all_channels
) > 0) {
2949 tor_log(severity
, LD_GENERAL
,
2950 "Channels have queued " U64_FORMAT
" bytes in " U64_FORMAT
" cells, "
2951 "and handed " U64_FORMAT
" bytes in " U64_FORMAT
" cells to the lower"
2953 U64_PRINTF_ARG(n_channel_bytes_queued
),
2954 U64_PRINTF_ARG(n_channel_cells_queued
),
2955 U64_PRINTF_ARG(n_channel_bytes_passed_to_lower_layer
),
2956 U64_PRINTF_ARG(n_channel_cells_passed_to_lower_layer
));
2957 tor_log(severity
, LD_GENERAL
,
2958 "There are currently " U64_FORMAT
" bytes in " U64_FORMAT
" cells "
2959 "in channel queues.",
2960 U64_PRINTF_ARG(n_channel_bytes_in_queues
),
2961 U64_PRINTF_ARG(n_channel_cells_in_queues
));
2962 tor_log(severity
, LD_GENERAL
,
2963 "Dumping statistics about %d channels:",
2964 smartlist_len(all_channels
));
2965 tor_log(severity
, LD_GENERAL
,
2966 "%d are active, and %d are done and waiting for cleanup",
2967 (active_channels
!= NULL
) ?
2968 smartlist_len(active_channels
) : 0,
2969 (finished_channels
!= NULL
) ?
2970 smartlist_len(finished_channels
) : 0);
2972 SMARTLIST_FOREACH(all_channels
, channel_t
*, chan
,
2973 channel_dump_statistics(chan
, severity
));
2975 tor_log(severity
, LD_GENERAL
,
2976 "Done spamming about channels now");
2978 tor_log(severity
, LD_GENERAL
,
2979 "No channels to dump");
2984 * Dump channel listener statistics to the log
2986 * This is called from dumpstats() in main.c and spams the log with
2987 * statistics on channel listeners.
2991 channel_listener_dumpstats(int severity
)
2993 if (all_listeners
&& smartlist_len(all_listeners
) > 0) {
2994 tor_log(severity
, LD_GENERAL
,
2995 "Dumping statistics about %d channel listeners:",
2996 smartlist_len(all_listeners
));
2997 tor_log(severity
, LD_GENERAL
,
2998 "%d are active and %d are done and waiting for cleanup",
2999 (active_listeners
!= NULL
) ?
3000 smartlist_len(active_listeners
) : 0,
3001 (finished_listeners
!= NULL
) ?
3002 smartlist_len(finished_listeners
) : 0);
3004 SMARTLIST_FOREACH(all_listeners
, channel_listener_t
*, chan_l
,
3005 channel_listener_dump_statistics(chan_l
, severity
));
3007 tor_log(severity
, LD_GENERAL
,
3008 "Done spamming about channel listeners now");
3010 tor_log(severity
, LD_GENERAL
,
3011 "No channel listeners to dump");
3016 * Set the cmux policy on all active channels
3020 channel_set_cmux_policy_everywhere(circuitmux_policy_t
*pol
)
3022 if (!active_channels
) return;
3024 SMARTLIST_FOREACH_BEGIN(active_channels
, channel_t
*, curr
) {
3026 circuitmux_set_policy(curr
->cmux
, pol
);
3028 } SMARTLIST_FOREACH_END(curr
);
3034 * This gets called periodically from run_scheduled_events() in main.c;
3035 * it cleans up after closed channels.
3039 channel_run_cleanup(void)
3041 channel_t
*tmp
= NULL
;
3043 /* Check if we need to do anything */
3044 if (!finished_channels
|| smartlist_len(finished_channels
) == 0) return;
3046 /* Iterate through finished_channels and get rid of them */
3047 SMARTLIST_FOREACH_BEGIN(finished_channels
, channel_t
*, curr
) {
3049 /* Remove it from the list */
3050 SMARTLIST_DEL_CURRENT(finished_channels
, curr
);
3051 /* Also unregister it */
3052 channel_unregister(tmp
);
3053 /* ... and free it */
3055 } SMARTLIST_FOREACH_END(curr
);
3059 * Clean up channel listeners
3061 * This gets called periodically from run_scheduled_events() in main.c;
3062 * it cleans up after closed channel listeners.
3066 channel_listener_run_cleanup(void)
3068 channel_listener_t
*tmp
= NULL
;
3070 /* Check if we need to do anything */
3071 if (!finished_listeners
|| smartlist_len(finished_listeners
) == 0) return;
3073 /* Iterate through finished_channels and get rid of them */
3074 SMARTLIST_FOREACH_BEGIN(finished_listeners
, channel_listener_t
*, curr
) {
3076 /* Remove it from the list */
3077 SMARTLIST_DEL_CURRENT(finished_listeners
, curr
);
3078 /* Also unregister it */
3079 channel_listener_unregister(tmp
);
3080 /* ... and free it */
3081 channel_listener_free(tmp
);
3082 } SMARTLIST_FOREACH_END(curr
);
3086 * Free a list of channels for channel_free_all()
3090 channel_free_list(smartlist_t
*channels
, int mark_for_close
)
3092 if (!channels
) return;
3094 SMARTLIST_FOREACH_BEGIN(channels
, channel_t
*, curr
) {
3095 /* Deregister and free it */
3097 log_debug(LD_CHANNEL
,
3098 "Cleaning up channel %p (global ID " U64_FORMAT
") "
3100 curr
, U64_PRINTF_ARG(curr
->global_identifier
),
3101 channel_state_to_string(curr
->state
), curr
->state
);
3102 /* Detach circuits early so they can find the channel */
3104 circuitmux_detach_all_circuits(curr
->cmux
, NULL
);
3106 SMARTLIST_DEL_CURRENT(channels
, curr
);
3107 channel_unregister(curr
);
3108 if (mark_for_close
) {
3109 if (!CHANNEL_CONDEMNED(curr
)) {
3110 channel_mark_for_close(curr
);
3112 channel_force_free(curr
);
3113 } else channel_free(curr
);
3114 } SMARTLIST_FOREACH_END(curr
);
3118 * Free a list of channel listeners for channel_free_all()
3122 channel_listener_free_list(smartlist_t
*listeners
, int mark_for_close
)
3124 if (!listeners
) return;
3126 SMARTLIST_FOREACH_BEGIN(listeners
, channel_listener_t
*, curr
) {
3127 /* Deregister and free it */
3129 log_debug(LD_CHANNEL
,
3130 "Cleaning up channel listener %p (global ID " U64_FORMAT
") "
3132 curr
, U64_PRINTF_ARG(curr
->global_identifier
),
3133 channel_listener_state_to_string(curr
->state
), curr
->state
);
3134 channel_listener_unregister(curr
);
3135 if (mark_for_close
) {
3136 if (!(curr
->state
== CHANNEL_LISTENER_STATE_CLOSING
||
3137 curr
->state
== CHANNEL_LISTENER_STATE_CLOSED
||
3138 curr
->state
== CHANNEL_LISTENER_STATE_ERROR
)) {
3139 channel_listener_mark_for_close(curr
);
3141 channel_listener_force_free(curr
);
3142 } else channel_listener_free(curr
);
3143 } SMARTLIST_FOREACH_END(curr
);
3147 * Close all channels and free everything
3149 * This gets called from tor_free_all() in main.c to clean up on exit.
3150 * It will close all registered channels and free associated storage,
3151 * then free the all_channels, active_channels, listening_channels and
3152 * finished_channels lists and also channel_identity_map.
3156 channel_free_all(void)
3158 log_debug(LD_CHANNEL
,
3159 "Shutting down channels...");
3161 /* First, let's go for finished channels */
3162 if (finished_channels
) {
3163 channel_free_list(finished_channels
, 0);
3164 smartlist_free(finished_channels
);
3165 finished_channels
= NULL
;
3168 /* Now the finished listeners */
3169 if (finished_listeners
) {
3170 channel_listener_free_list(finished_listeners
, 0);
3171 smartlist_free(finished_listeners
);
3172 finished_listeners
= NULL
;
3175 /* Now all active channels */
3176 if (active_channels
) {
3177 channel_free_list(active_channels
, 1);
3178 smartlist_free(active_channels
);
3179 active_channels
= NULL
;
3182 /* Now all active listeners */
3183 if (active_listeners
) {
3184 channel_listener_free_list(active_listeners
, 1);
3185 smartlist_free(active_listeners
);
3186 active_listeners
= NULL
;
3189 /* Now all channels, in case any are left over */
3191 channel_free_list(all_channels
, 1);
3192 smartlist_free(all_channels
);
3193 all_channels
= NULL
;
3196 /* Now all listeners, in case any are left over */
3197 if (all_listeners
) {
3198 channel_listener_free_list(all_listeners
, 1);
3199 smartlist_free(all_listeners
);
3200 all_listeners
= NULL
;
3203 /* Now free channel_identity_map */
3204 log_debug(LD_CHANNEL
,
3205 "Freeing channel_identity_map");
3206 /* Geez, anything still left over just won't die ... let it leak then */
3207 HT_CLEAR(channel_idmap
, &channel_identity_map
);
3209 log_debug(LD_CHANNEL
,
3210 "Done cleaning up after channels");
3214 * Connect to a given addr/port/digest
3216 * This sets up a new outgoing channel; in the future if multiple
3217 * channel_t subclasses are available, this is where the selection policy
3218 * should go. It may also be desirable to fold port into tor_addr_t
3219 * or make a new type including a tor_addr_t and port, so we have a
3220 * single abstract object encapsulating all the protocol details of
3221 * how to contact an OR.
3225 channel_connect(const tor_addr_t
*addr
, uint16_t port
,
3226 const char *id_digest
)
3228 return channel_tls_connect(addr
, port
, id_digest
);
3232 * Decide which of two channels to prefer for extending a circuit
3234 * This function is called while extending a circuit and returns true iff
3235 * a is 'better' than b. The most important criterion here is that a
3236 * canonical channel is always better than a non-canonical one, but the
3237 * number of circuits and the age are used as tie-breakers.
3239 * This is based on the former connection_or_is_better() of connection_or.c
3243 channel_is_better(time_t now
, channel_t
*a
, channel_t
*b
,
3244 int forgive_new_connections
)
3246 int a_grace
, b_grace
;
3247 int a_is_canonical
, b_is_canonical
;
3248 int a_has_circs
, b_has_circs
;
3251 * Do not definitively deprecate a new channel with no circuits on it
3252 * until this much time has passed.
3254 #define NEW_CHAN_GRACE_PERIOD (15*60)
3259 /* Check if one is canonical and the other isn't first */
3260 a_is_canonical
= channel_is_canonical(a
);
3261 b_is_canonical
= channel_is_canonical(b
);
3263 if (a_is_canonical
&& !b_is_canonical
) return 1;
3264 if (!a_is_canonical
&& b_is_canonical
) return 0;
3267 * Okay, if we're here they tied on canonicity. Next we check if
3268 * they have any circuits, and if one does and the other doesn't,
3269 * we prefer the one that does, unless we are forgiving and the
3270 * one that has no circuits is in its grace period.
3273 a_has_circs
= (channel_num_circuits(a
) > 0);
3274 b_has_circs
= (channel_num_circuits(b
) > 0);
3275 a_grace
= (forgive_new_connections
&&
3276 (now
< channel_when_created(a
) + NEW_CHAN_GRACE_PERIOD
));
3277 b_grace
= (forgive_new_connections
&&
3278 (now
< channel_when_created(b
) + NEW_CHAN_GRACE_PERIOD
));
3280 if (a_has_circs
&& !b_has_circs
&& !b_grace
) return 1;
3281 if (!a_has_circs
&& b_has_circs
&& !a_grace
) return 0;
3283 /* They tied on circuits too; just prefer whichever is newer */
3285 if (channel_when_created(a
) > channel_when_created(b
)) return 1;
3290 * Get a channel to extend a circuit
3292 * Pick a suitable channel to extend a circuit to given the desired digest
3293 * the address we believe is correct for that digest; this tries to see
3294 * if we already have one for the requested endpoint, but if there is no good
3295 * channel, set *msg_out to a message describing the channel's state
3296 * and our next action, and set *launch_out to a boolean indicated whether
3297 * the caller should try to launch a new channel with channel_connect().
3301 channel_get_for_extend(const char *digest
,
3302 const tor_addr_t
*target_addr
,
3303 const char **msg_out
,
3306 channel_t
*chan
, *best
= NULL
;
3307 int n_inprogress_goodaddr
= 0, n_old
= 0;
3308 int n_noncanonical
= 0, n_possible
= 0;
3309 time_t now
= approx_time();
3311 tor_assert(msg_out
);
3312 tor_assert(launch_out
);
3314 chan
= channel_find_by_remote_digest(digest
);
3316 /* Walk the list, unrefing the old one and refing the new at each
3319 for (; chan
; chan
= channel_next_with_digest(chan
)) {
3320 tor_assert(tor_memeq(chan
->identity_digest
,
3321 digest
, DIGEST_LEN
));
3323 if (CHANNEL_CONDEMNED(chan
))
3326 /* Never return a channel on which the other end appears to be
3328 if (channel_is_client(chan
)) {
3332 /* Never return a non-open connection. */
3333 if (!CHANNEL_IS_OPEN(chan
)) {
3334 /* If the address matches, don't launch a new connection for this
3336 if (channel_matches_target_addr_for_extend(chan
, target_addr
))
3337 ++n_inprogress_goodaddr
;
3341 /* Never return a connection that shouldn't be used for circs. */
3342 if (channel_is_bad_for_new_circs(chan
)) {
3347 /* Never return a non-canonical connection using a recent link protocol
3348 * if the address is not what we wanted.
3350 * The channel_is_canonical_is_reliable() function asks the lower layer
3351 * if we should trust channel_is_canonical(). The below is from the
3352 * comments of the old circuit_or_get_for_extend() and applies when
3353 * the lower-layer transport is channel_tls_t.
3355 * (For old link protocols, we can't rely on is_canonical getting
3356 * set properly if we're talking to the right address, since we might
3357 * have an out-of-date descriptor, and we will get no NETINFO cell to
3358 * tell us about the right address.)
3360 if (!channel_is_canonical(chan
) &&
3361 channel_is_canonical_is_reliable(chan
) &&
3362 !channel_matches_target_addr_for_extend(chan
, target_addr
)) {
3370 best
= chan
; /* If we have no 'best' so far, this one is good enough. */
3374 if (channel_is_better(now
, chan
, best
, 0))
3379 *msg_out
= "Connection is fine; using it.";
3382 } else if (n_inprogress_goodaddr
) {
3383 *msg_out
= "Connection in progress; waiting.";
3386 } else if (n_old
|| n_noncanonical
) {
3387 *msg_out
= "Connections all too old, or too non-canonical. "
3388 " Launching a new one.";
3392 *msg_out
= "Not connected. Connecting.";
3399 * Describe the transport subclass for a channel
3401 * Invoke a method to get a string description of the lower-layer
3402 * transport for this channel.
3406 channel_describe_transport(channel_t
*chan
)
3409 tor_assert(chan
->describe_transport
);
3411 return chan
->describe_transport(chan
);
3415 * Describe the transport subclass for a channel listener
3417 * Invoke a method to get a string description of the lower-layer
3418 * transport for this channel listener.
3422 channel_listener_describe_transport(channel_listener_t
*chan_l
)
3425 tor_assert(chan_l
->describe_transport
);
3427 return chan_l
->describe_transport(chan_l
);
3431 * Return the number of entries in <b>queue</b>
3434 chan_cell_queue_len(const chan_cell_queue_t
*queue
)
3437 cell_queue_entry_t
*cell
;
3438 TOR_SIMPLEQ_FOREACH(cell
, queue
, next
)
3444 * Dump channel statistics
3446 * Dump statistics for one channel to the log
3450 channel_dump_statistics
, (channel_t
*chan
, int severity
))
3452 double avg
, interval
, age
;
3453 time_t now
= time(NULL
);
3454 tor_addr_t remote_addr
;
3455 int have_remote_addr
;
3456 char *remote_addr_str
;
3460 age
= (double)(now
- chan
->timestamp_created
);
3462 tor_log(severity
, LD_GENERAL
,
3463 "Channel " U64_FORMAT
" (at %p) with transport %s is in state "
3465 U64_PRINTF_ARG(chan
->global_identifier
), chan
,
3466 channel_describe_transport(chan
),
3467 channel_state_to_string(chan
->state
), chan
->state
);
3468 tor_log(severity
, LD_GENERAL
,
3469 " * Channel " U64_FORMAT
" was created at " U64_FORMAT
3470 " (" U64_FORMAT
" seconds ago) "
3471 "and last active at " U64_FORMAT
" (" U64_FORMAT
" seconds ago)",
3472 U64_PRINTF_ARG(chan
->global_identifier
),
3473 U64_PRINTF_ARG(chan
->timestamp_created
),
3474 U64_PRINTF_ARG(now
- chan
->timestamp_created
),
3475 U64_PRINTF_ARG(chan
->timestamp_active
),
3476 U64_PRINTF_ARG(now
- chan
->timestamp_active
));
3478 /* Handle digest and nickname */
3479 if (!tor_digest_is_zero(chan
->identity_digest
)) {
3480 if (chan
->nickname
) {
3481 tor_log(severity
, LD_GENERAL
,
3482 " * Channel " U64_FORMAT
" says it is connected "
3483 "to an OR with digest %s and nickname %s",
3484 U64_PRINTF_ARG(chan
->global_identifier
),
3485 hex_str(chan
->identity_digest
, DIGEST_LEN
),
3488 tor_log(severity
, LD_GENERAL
,
3489 " * Channel " U64_FORMAT
" says it is connected "
3490 "to an OR with digest %s and no known nickname",
3491 U64_PRINTF_ARG(chan
->global_identifier
),
3492 hex_str(chan
->identity_digest
, DIGEST_LEN
));
3495 if (chan
->nickname
) {
3496 tor_log(severity
, LD_GENERAL
,
3497 " * Channel " U64_FORMAT
" does not know the digest"
3498 " of the OR it is connected to, but reports its nickname is %s",
3499 U64_PRINTF_ARG(chan
->global_identifier
),
3502 tor_log(severity
, LD_GENERAL
,
3503 " * Channel " U64_FORMAT
" does not know the digest"
3504 " or the nickname of the OR it is connected to",
3505 U64_PRINTF_ARG(chan
->global_identifier
));
3509 /* Handle remote address and descriptions */
3510 have_remote_addr
= channel_get_addr_if_possible(chan
, &remote_addr
);
3511 if (have_remote_addr
) {
3512 char *actual
= tor_strdup(channel_get_actual_remote_descr(chan
));
3513 remote_addr_str
= tor_addr_to_str_dup(&remote_addr
);
3514 tor_log(severity
, LD_GENERAL
,
3515 " * Channel " U64_FORMAT
" says its remote address"
3516 " is %s, and gives a canonical description of \"%s\" and an "
3517 "actual description of \"%s\"",
3518 U64_PRINTF_ARG(chan
->global_identifier
),
3519 safe_str(remote_addr_str
),
3520 safe_str(channel_get_canonical_remote_descr(chan
)),
3522 tor_free(remote_addr_str
);
3525 char *actual
= tor_strdup(channel_get_actual_remote_descr(chan
));
3526 tor_log(severity
, LD_GENERAL
,
3527 " * Channel " U64_FORMAT
" does not know its remote "
3528 "address, but gives a canonical description of \"%s\" and an "
3529 "actual description of \"%s\"",
3530 U64_PRINTF_ARG(chan
->global_identifier
),
3531 channel_get_canonical_remote_descr(chan
),
3537 tor_log(severity
, LD_GENERAL
,
3538 " * Channel " U64_FORMAT
" has these marks: %s %s %s "
3540 U64_PRINTF_ARG(chan
->global_identifier
),
3541 channel_is_bad_for_new_circs(chan
) ?
3542 "bad_for_new_circs" : "!bad_for_new_circs",
3543 channel_is_canonical(chan
) ?
3544 "canonical" : "!canonical",
3545 channel_is_canonical_is_reliable(chan
) ?
3546 "is_canonical_is_reliable" :
3547 "!is_canonical_is_reliable",
3548 channel_is_client(chan
) ?
3549 "client" : "!client",
3550 channel_is_local(chan
) ?
3552 channel_is_incoming(chan
) ?
3553 "incoming" : "outgoing");
3555 /* Describe queues */
3556 tor_log(severity
, LD_GENERAL
,
3557 " * Channel " U64_FORMAT
" has %d queued incoming cells"
3558 " and %d queued outgoing cells",
3559 U64_PRINTF_ARG(chan
->global_identifier
),
3560 chan_cell_queue_len(&chan
->incoming_queue
),
3561 chan_cell_queue_len(&chan
->outgoing_queue
));
3563 /* Describe circuits */
3564 tor_log(severity
, LD_GENERAL
,
3565 " * Channel " U64_FORMAT
" has %d active circuits out of"
3567 U64_PRINTF_ARG(chan
->global_identifier
),
3568 (chan
->cmux
!= NULL
) ?
3569 circuitmux_num_active_circuits(chan
->cmux
) : 0,
3570 (chan
->cmux
!= NULL
) ?
3571 circuitmux_num_circuits(chan
->cmux
) : 0);
3573 /* Describe timestamps */
3574 tor_log(severity
, LD_GENERAL
,
3575 " * Channel " U64_FORMAT
" was last used by a "
3576 "client at " U64_FORMAT
" (" U64_FORMAT
" seconds ago)",
3577 U64_PRINTF_ARG(chan
->global_identifier
),
3578 U64_PRINTF_ARG(chan
->timestamp_client
),
3579 U64_PRINTF_ARG(now
- chan
->timestamp_client
));
3580 tor_log(severity
, LD_GENERAL
,
3581 " * Channel " U64_FORMAT
" was last drained at "
3582 U64_FORMAT
" (" U64_FORMAT
" seconds ago)",
3583 U64_PRINTF_ARG(chan
->global_identifier
),
3584 U64_PRINTF_ARG(chan
->timestamp_drained
),
3585 U64_PRINTF_ARG(now
- chan
->timestamp_drained
));
3586 tor_log(severity
, LD_GENERAL
,
3587 " * Channel " U64_FORMAT
" last received a cell "
3588 "at " U64_FORMAT
" (" U64_FORMAT
" seconds ago)",
3589 U64_PRINTF_ARG(chan
->global_identifier
),
3590 U64_PRINTF_ARG(chan
->timestamp_recv
),
3591 U64_PRINTF_ARG(now
- chan
->timestamp_recv
));
3592 tor_log(severity
, LD_GENERAL
,
3593 " * Channel " U64_FORMAT
" last transmitted a cell "
3594 "at " U64_FORMAT
" (" U64_FORMAT
" seconds ago)",
3595 U64_PRINTF_ARG(chan
->global_identifier
),
3596 U64_PRINTF_ARG(chan
->timestamp_xmit
),
3597 U64_PRINTF_ARG(now
- chan
->timestamp_xmit
));
3599 /* Describe counters and rates */
3600 tor_log(severity
, LD_GENERAL
,
3601 " * Channel " U64_FORMAT
" has received "
3602 U64_FORMAT
" bytes in " U64_FORMAT
" cells and transmitted "
3603 U64_FORMAT
" bytes in " U64_FORMAT
" cells",
3604 U64_PRINTF_ARG(chan
->global_identifier
),
3605 U64_PRINTF_ARG(chan
->n_bytes_recved
),
3606 U64_PRINTF_ARG(chan
->n_cells_recved
),
3607 U64_PRINTF_ARG(chan
->n_bytes_xmitted
),
3608 U64_PRINTF_ARG(chan
->n_cells_xmitted
));
3609 if (now
> chan
->timestamp_created
&&
3610 chan
->timestamp_created
> 0) {
3611 if (chan
->n_bytes_recved
> 0) {
3612 avg
= (double)(chan
->n_bytes_recved
) / age
;
3613 tor_log(severity
, LD_GENERAL
,
3614 " * Channel " U64_FORMAT
" has averaged %f "
3615 "bytes received per second",
3616 U64_PRINTF_ARG(chan
->global_identifier
), avg
);
3618 if (chan
->n_cells_recved
> 0) {
3619 avg
= (double)(chan
->n_cells_recved
) / age
;
3621 tor_log(severity
, LD_GENERAL
,
3622 " * Channel " U64_FORMAT
" has averaged %f "
3623 "cells received per second",
3624 U64_PRINTF_ARG(chan
->global_identifier
), avg
);
3625 } else if (avg
>= 0.0) {
3626 interval
= 1.0 / avg
;
3627 tor_log(severity
, LD_GENERAL
,
3628 " * Channel " U64_FORMAT
" has averaged %f "
3629 "seconds between received cells",
3630 U64_PRINTF_ARG(chan
->global_identifier
), interval
);
3633 if (chan
->n_bytes_xmitted
> 0) {
3634 avg
= (double)(chan
->n_bytes_xmitted
) / age
;
3635 tor_log(severity
, LD_GENERAL
,
3636 " * Channel " U64_FORMAT
" has averaged %f "
3637 "bytes transmitted per second",
3638 U64_PRINTF_ARG(chan
->global_identifier
), avg
);
3640 if (chan
->n_cells_xmitted
> 0) {
3641 avg
= (double)(chan
->n_cells_xmitted
) / age
;
3643 tor_log(severity
, LD_GENERAL
,
3644 " * Channel " U64_FORMAT
" has averaged %f "
3645 "cells transmitted per second",
3646 U64_PRINTF_ARG(chan
->global_identifier
), avg
);
3647 } else if (avg
>= 0.0) {
3648 interval
= 1.0 / avg
;
3649 tor_log(severity
, LD_GENERAL
,
3650 " * Channel " U64_FORMAT
" has averaged %f "
3651 "seconds between transmitted cells",
3652 U64_PRINTF_ARG(chan
->global_identifier
), interval
);
3657 /* Dump anything the lower layer has to say */
3658 channel_dump_transport_statistics(chan
, severity
);
3662 * Dump channel listener statistics
3664 * Dump statistics for one channel listener to the log
3668 channel_listener_dump_statistics(channel_listener_t
*chan_l
, int severity
)
3670 double avg
, interval
, age
;
3671 time_t now
= time(NULL
);
3675 age
= (double)(now
- chan_l
->timestamp_created
);
3677 tor_log(severity
, LD_GENERAL
,
3678 "Channel listener " U64_FORMAT
" (at %p) with transport %s is in "
3680 U64_PRINTF_ARG(chan_l
->global_identifier
), chan_l
,
3681 channel_listener_describe_transport(chan_l
),
3682 channel_listener_state_to_string(chan_l
->state
), chan_l
->state
);
3683 tor_log(severity
, LD_GENERAL
,
3684 " * Channel listener " U64_FORMAT
" was created at " U64_FORMAT
3685 " (" U64_FORMAT
" seconds ago) "
3686 "and last active at " U64_FORMAT
" (" U64_FORMAT
" seconds ago)",
3687 U64_PRINTF_ARG(chan_l
->global_identifier
),
3688 U64_PRINTF_ARG(chan_l
->timestamp_created
),
3689 U64_PRINTF_ARG(now
- chan_l
->timestamp_created
),
3690 U64_PRINTF_ARG(chan_l
->timestamp_active
),
3691 U64_PRINTF_ARG(now
- chan_l
->timestamp_active
));
3693 tor_log(severity
, LD_GENERAL
,
3694 " * Channel listener " U64_FORMAT
" last accepted an incoming "
3695 "channel at " U64_FORMAT
" (" U64_FORMAT
" seconds ago) "
3696 "and has accepted " U64_FORMAT
" channels in total",
3697 U64_PRINTF_ARG(chan_l
->global_identifier
),
3698 U64_PRINTF_ARG(chan_l
->timestamp_accepted
),
3699 U64_PRINTF_ARG(now
- chan_l
->timestamp_accepted
),
3700 U64_PRINTF_ARG(chan_l
->n_accepted
));
3703 * If it's sensible to do so, get the rate of incoming channels on this
3706 if (now
> chan_l
->timestamp_created
&&
3707 chan_l
->timestamp_created
> 0 &&
3708 chan_l
->n_accepted
> 0) {
3709 avg
= (double)(chan_l
->n_accepted
) / age
;
3711 tor_log(severity
, LD_GENERAL
,
3712 " * Channel listener " U64_FORMAT
" has averaged %f incoming "
3713 "channels per second",
3714 U64_PRINTF_ARG(chan_l
->global_identifier
), avg
);
3715 } else if (avg
>= 0.0) {
3716 interval
= 1.0 / avg
;
3717 tor_log(severity
, LD_GENERAL
,
3718 " * Channel listener " U64_FORMAT
" has averaged %f seconds "
3719 "between incoming channels",
3720 U64_PRINTF_ARG(chan_l
->global_identifier
), interval
);
3724 /* Dump anything the lower layer has to say */
3725 channel_listener_dump_transport_statistics(chan_l
, severity
);
3729 * Invoke transport-specific stats dump for channel
3731 * If there is a lower-layer statistics dump method, invoke it
3735 channel_dump_transport_statistics(channel_t
*chan
, int severity
)
3739 if (chan
->dumpstats
) chan
->dumpstats(chan
, severity
);
3743 * Invoke transport-specific stats dump for channel listener
3745 * If there is a lower-layer statistics dump method, invoke it
3749 channel_listener_dump_transport_statistics(channel_listener_t
*chan_l
,
3754 if (chan_l
->dumpstats
) chan_l
->dumpstats(chan_l
, severity
);
3758 * Return text description of the remote endpoint
3760 * This function return a test provided by the lower layer of the remote
3761 * endpoint for this channel; it should specify the actual address connected
3764 * Subsequent calls to channel_get_{actual,canonical}_remote_{address,descr}
3765 * may invalidate the return value from this function.
3768 channel_get_actual_remote_descr(channel_t
*chan
)
3771 tor_assert(chan
->get_remote_descr
);
3773 /* Param 1 indicates the actual description */
3774 return chan
->get_remote_descr(chan
, GRD_FLAG_ORIGINAL
);
3778 * Return the text address of the remote endpoint.
3780 * Subsequent calls to channel_get_{actual,canonical}_remote_{address,descr}
3781 * may invalidate the return value from this function.
3784 channel_get_actual_remote_address(channel_t
*chan
)
3786 /* Param 1 indicates the actual description */
3787 return chan
->get_remote_descr(chan
, GRD_FLAG_ORIGINAL
|GRD_FLAG_ADDR_ONLY
);
3791 * Return text description of the remote endpoint canonical address
3793 * This function return a test provided by the lower layer of the remote
3794 * endpoint for this channel; it should use the known canonical address for
3795 * this OR's identity digest if possible.
3797 * Subsequent calls to channel_get_{actual,canonical}_remote_{address,descr}
3798 * may invalidate the return value from this function.
3801 channel_get_canonical_remote_descr(channel_t
*chan
)
3804 tor_assert(chan
->get_remote_descr
);
3806 /* Param 0 indicates the canonicalized description */
3807 return chan
->get_remote_descr(chan
, 0);
3811 * Get remote address if possible.
3813 * Write the remote address out to a tor_addr_t if the underlying transport
3814 * supports this operation, and return 1. Return 0 if the underlying transport
3815 * doesn't let us do this.
3818 channel_get_addr_if_possible(channel_t
*chan
, tor_addr_t
*addr_out
)
3821 tor_assert(addr_out
);
3823 if (chan
->get_remote_addr
)
3824 return chan
->get_remote_addr(chan
, addr_out
);
3825 /* Else no support, method not implemented */
3830 * Check if there are outgoing queue writes on this channel
3832 * Indicate if either we have queued cells, or if not, whether the underlying
3833 * lower-layer transport thinks it has an output queue.
3837 channel_has_queued_writes(channel_t
*chan
)
3842 tor_assert(chan
->has_queued_writes
);
3844 if (! TOR_SIMPLEQ_EMPTY(&chan
->outgoing_queue
)) {
3847 /* Check with the lower layer */
3848 has_writes
= chan
->has_queued_writes(chan
);
3855 * Check the is_bad_for_new_circs flag
3857 * This function returns the is_bad_for_new_circs flag of the specified
3862 channel_is_bad_for_new_circs(channel_t
*chan
)
3866 return chan
->is_bad_for_new_circs
;
3870 * Mark a channel as bad for new circuits
3872 * Set the is_bad_for_new_circs_flag on chan.
3876 channel_mark_bad_for_new_circs(channel_t
*chan
)
3880 chan
->is_bad_for_new_circs
= 1;
3884 * Get the client flag
3886 * This returns the client flag of a channel, which will be set if
3887 * command_process_create_cell() in command.c thinks this is a connection
3892 channel_is_client(channel_t
*chan
)
3896 return chan
->is_client
;
3900 * Set the client flag
3902 * Mark a channel as being from a client
3906 channel_mark_client(channel_t
*chan
)
3910 chan
->is_client
= 1;
3914 * Get the canonical flag for a channel
3916 * This returns the is_canonical for a channel; this flag is determined by
3917 * the lower layer and can't be set in a transport-independent way.
3921 channel_is_canonical(channel_t
*chan
)
3924 tor_assert(chan
->is_canonical
);
3926 return chan
->is_canonical(chan
, 0);
3930 * Test if the canonical flag is reliable
3932 * This function asks if the lower layer thinks it's safe to trust the
3933 * result of channel_is_canonical()
3937 channel_is_canonical_is_reliable(channel_t
*chan
)
3940 tor_assert(chan
->is_canonical
);
3942 return chan
->is_canonical(chan
, 1);
3946 * Test incoming flag
3948 * This function gets the incoming flag; this is set when a listener spawns
3949 * a channel. If this returns true the channel was remotely initiated.
3953 channel_is_incoming(channel_t
*chan
)
3957 return chan
->is_incoming
;
3961 * Set the incoming flag
3963 * This function is called when a channel arrives on a listening channel
3964 * to mark it as incoming.
3968 channel_mark_incoming(channel_t
*chan
)
3972 chan
->is_incoming
= 1;
3978 * This function gets the local flag; the lower layer should set this when
3979 * setting up the channel if is_local_addr() is true for all of the
3980 * destinations it will communicate with on behalf of this channel. It's
3981 * used to decide whether to declare the network reachable when seeing incoming
3982 * traffic on the channel.
3986 channel_is_local(channel_t
*chan
)
3990 return chan
->is_local
;
3994 * Set the local flag
3996 * This internal-only function should be called by the lower layer if the
3997 * channel is to a local address. See channel_is_local() above or the
3998 * description of the is_local bit in channel.h
4002 channel_mark_local(channel_t
*chan
)
4010 * Mark a channel as remote
4012 * This internal-only function should be called by the lower layer if the
4013 * channel is not to a local address but has previously been marked local.
4014 * See channel_is_local() above or the description of the is_local bit in
4019 channel_mark_remote(channel_t
*chan
)
4027 * Test outgoing flag
4029 * This function gets the outgoing flag; this is the inverse of the incoming
4030 * bit set when a listener spawns a channel. If this returns true the channel
4031 * was locally initiated.
4035 channel_is_outgoing(channel_t
*chan
)
4039 return !(chan
->is_incoming
);
4043 * Mark a channel as outgoing
4045 * This function clears the incoming flag and thus marks a channel as
4050 channel_mark_outgoing(channel_t
*chan
)
4054 chan
->is_incoming
= 0;
4057 /************************
4058 * Flow control queries *
4059 ***********************/
4062 * Get the latest estimate for the total queue size of all open channels
4066 channel_get_global_queue_estimate(void)
4068 return estimated_total_queue_size
;
4072 * Estimate the number of writeable cells
4074 * Ask the lower layer for an estimate of how many cells it can accept, and
4075 * then subtract the length of our outgoing_queue, if any, to produce an
4076 * estimate of the number of cells this channel can accept for writes.
4080 channel_num_cells_writeable(channel_t
*chan
)
4085 tor_assert(chan
->num_cells_writeable
);
4087 if (chan
->state
== CHANNEL_STATE_OPEN
) {
4088 /* Query lower layer */
4089 result
= chan
->num_cells_writeable(chan
);
4090 /* Subtract cell queue length, if any */
4091 result
-= chan_cell_queue_len(&chan
->outgoing_queue
);
4092 if (result
< 0) result
= 0;
4094 /* No cells are writeable in any other state */
4101 /*********************
4102 * Timestamp updates *
4103 ********************/
4106 * Update the created timestamp for a channel
4108 * This updates the channel's created timestamp and should only be called
4109 * from channel_init().
4113 channel_timestamp_created(channel_t
*chan
)
4115 time_t now
= time(NULL
);
4119 chan
->timestamp_created
= now
;
4123 * Update the created timestamp for a channel listener
4125 * This updates the channel listener's created timestamp and should only be
4126 * called from channel_init_listener().
4130 channel_listener_timestamp_created(channel_listener_t
*chan_l
)
4132 time_t now
= time(NULL
);
4136 chan_l
->timestamp_created
= now
;
4140 * Update the last active timestamp for a channel
4142 * This function updates the channel's last active timestamp; it should be
4143 * called by the lower layer whenever there is activity on the channel which
4144 * does not lead to a cell being transmitted or received; the active timestamp
4145 * is also updated from channel_timestamp_recv() and channel_timestamp_xmit(),
4146 * but it should be updated for things like the v3 handshake and stuff that
4147 * produce activity only visible to the lower layer.
4151 channel_timestamp_active(channel_t
*chan
)
4153 time_t now
= time(NULL
);
4157 chan
->timestamp_active
= now
;
4161 * Update the last active timestamp for a channel listener
4165 channel_listener_timestamp_active(channel_listener_t
*chan_l
)
4167 time_t now
= time(NULL
);
4171 chan_l
->timestamp_active
= now
;
4175 * Update the last accepted timestamp.
4177 * This function updates the channel listener's last accepted timestamp; it
4178 * should be called whenever a new incoming channel is accepted on a
4183 channel_listener_timestamp_accepted(channel_listener_t
*chan_l
)
4185 time_t now
= time(NULL
);
4189 chan_l
->timestamp_active
= now
;
4190 chan_l
->timestamp_accepted
= now
;
4194 * Update client timestamp
4196 * This function is called by relay.c to timestamp a channel that appears to
4197 * be used as a client.
4201 channel_timestamp_client(channel_t
*chan
)
4203 time_t now
= time(NULL
);
4207 chan
->timestamp_client
= now
;
4211 * Update the last drained timestamp
4213 * This is called whenever we transmit a cell which leaves the outgoing cell
4214 * queue completely empty. It also updates the xmit time and the active time.
4218 channel_timestamp_drained(channel_t
*chan
)
4220 time_t now
= time(NULL
);
4224 chan
->timestamp_active
= now
;
4225 chan
->timestamp_drained
= now
;
4226 chan
->timestamp_xmit
= now
;
4230 * Update the recv timestamp
4232 * This is called whenever we get an incoming cell from the lower layer.
4233 * This also updates the active timestamp.
4237 channel_timestamp_recv(channel_t
*chan
)
4239 time_t now
= time(NULL
);
4243 chan
->timestamp_active
= now
;
4244 chan
->timestamp_recv
= now
;
4248 * Update the xmit timestamp
4249 * This is called whenever we pass an outgoing cell to the lower layer. This
4250 * also updates the active timestamp.
4254 channel_timestamp_xmit(channel_t
*chan
)
4256 time_t now
= time(NULL
);
4260 chan
->timestamp_active
= now
;
4261 chan
->timestamp_xmit
= now
;
4264 /***************************************************************
4265 * Timestamp queries - see above for definitions of timestamps *
4266 **************************************************************/
4269 * Query created timestamp for a channel
4273 channel_when_created(channel_t
*chan
)
4277 return chan
->timestamp_created
;
4281 * Query created timestamp for a channel listener
4285 channel_listener_when_created(channel_listener_t
*chan_l
)
4289 return chan_l
->timestamp_created
;
4293 * Query last active timestamp for a channel
4297 channel_when_last_active(channel_t
*chan
)
4301 return chan
->timestamp_active
;
4305 * Query last active timestamp for a channel listener
4309 channel_listener_when_last_active(channel_listener_t
*chan_l
)
4313 return chan_l
->timestamp_active
;
4317 * Query last accepted timestamp for a channel listener
4321 channel_listener_when_last_accepted(channel_listener_t
*chan_l
)
4325 return chan_l
->timestamp_accepted
;
4329 * Query client timestamp
4333 channel_when_last_client(channel_t
*chan
)
4337 return chan
->timestamp_client
;
4341 * Query drained timestamp
4345 channel_when_last_drained(channel_t
*chan
)
4349 return chan
->timestamp_drained
;
4353 * Query recv timestamp
4357 channel_when_last_recv(channel_t
*chan
)
4361 return chan
->timestamp_recv
;
4365 * Query xmit timestamp
4369 channel_when_last_xmit(channel_t
*chan
)
4373 return chan
->timestamp_xmit
;
4377 * Query accepted counter
4381 channel_listener_count_accepted(channel_listener_t
*chan_l
)
4385 return chan_l
->n_accepted
;
4389 * Query received cell counter
4393 channel_count_recved(channel_t
*chan
)
4397 return chan
->n_cells_recved
;
4401 * Query transmitted cell counter
4405 channel_count_xmitted(channel_t
*chan
)
4409 return chan
->n_cells_xmitted
;
4413 * Check if a channel matches an extend_info_t
4415 * This function calls the lower layer and asks if this channel matches a
4416 * given extend_info_t.
4420 channel_matches_extend_info(channel_t
*chan
, extend_info_t
*extend_info
)
4423 tor_assert(chan
->matches_extend_info
);
4424 tor_assert(extend_info
);
4426 return chan
->matches_extend_info(chan
, extend_info
);
4430 * Check if a channel matches a given target address; return true iff we do.
4432 * This function calls into the lower layer and asks if this channel thinks
4433 * it matches a given target address for circuit extension purposes.
4437 channel_matches_target_addr_for_extend(channel_t
*chan
,
4438 const tor_addr_t
*target
)
4441 tor_assert(chan
->matches_target
);
4444 return chan
->matches_target(chan
, target
);
4448 * Return the total number of circuits used by a channel
4450 * @param chan Channel to query
4451 * @return Number of circuits using this as n_chan or p_chan
4455 channel_num_circuits(channel_t
*chan
)
4459 return chan
->num_n_circuits
+
4460 chan
->num_p_circuits
;
4464 * Set up circuit ID generation
4466 * This is called when setting up a channel and replaces the old
4467 * connection_or_set_circid_type()
4470 channel_set_circid_type
,(channel_t
*chan
,
4471 crypto_pk_t
*identity_rcvd
,
4472 int consider_identity
))
4475 crypto_pk_t
*our_identity
;
4479 started_here
= channel_is_outgoing(chan
);
4481 if (! consider_identity
) {
4483 chan
->circ_id_type
= CIRC_ID_TYPE_HIGHER
;
4485 chan
->circ_id_type
= CIRC_ID_TYPE_LOWER
;
4489 our_identity
= started_here
?
4490 get_tlsclient_identity_key() : get_server_identity_key();
4492 if (identity_rcvd
) {
4493 if (crypto_pk_cmp_keys(our_identity
, identity_rcvd
) < 0) {
4494 chan
->circ_id_type
= CIRC_ID_TYPE_LOWER
;
4496 chan
->circ_id_type
= CIRC_ID_TYPE_HIGHER
;
4499 chan
->circ_id_type
= CIRC_ID_TYPE_NEITHER
;
4504 * Update the estimated number of bytes queued to transmit for this channel,
4505 * and notify the scheduler. The estimate includes both the channel queue and
4506 * the queue size reported by the lower layer, and an overhead estimate
4507 * optionally provided by the lower layer.
4511 channel_update_xmit_queue_size(channel_t
*chan
)
4513 uint64_t queued
, adj
;
4517 tor_assert(chan
->num_bytes_queued
);
4520 * First, get the number of bytes we have queued without factoring in
4521 * lower-layer overhead.
4523 queued
= chan
->num_bytes_queued(chan
) + chan
->bytes_in_queue
;
4524 /* Next, adjust by the overhead factor, if any is available */
4525 if (chan
->get_overhead_estimate
) {
4526 overhead
= chan
->get_overhead_estimate(chan
);
4527 if (overhead
>= 1.0) {
4528 queued
= (uint64_t)(queued
* overhead
);
4530 /* Ignore silly overhead factors */
4531 log_notice(LD_CHANNEL
, "Ignoring silly overhead factor %f", overhead
);
4535 /* Now, compare to the previous estimate */
4536 if (queued
> chan
->bytes_queued_for_xmit
) {
4537 adj
= queued
- chan
->bytes_queued_for_xmit
;
4538 log_debug(LD_CHANNEL
,
4539 "Increasing queue size for channel " U64_FORMAT
" by " U64_FORMAT
4540 " from " U64_FORMAT
" to " U64_FORMAT
,
4541 U64_PRINTF_ARG(chan
->global_identifier
),
4542 U64_PRINTF_ARG(adj
),
4543 U64_PRINTF_ARG(chan
->bytes_queued_for_xmit
),
4544 U64_PRINTF_ARG(queued
));
4545 /* Update the channel's estimate */
4546 chan
->bytes_queued_for_xmit
= queued
;
4548 /* Update the global queue size estimate if appropriate */
4549 if (chan
->state
== CHANNEL_STATE_OPEN
||
4550 chan
->state
== CHANNEL_STATE_MAINT
) {
4551 estimated_total_queue_size
+= adj
;
4552 log_debug(LD_CHANNEL
,
4553 "Increasing global queue size by " U64_FORMAT
" for channel "
4554 U64_FORMAT
", new size is " U64_FORMAT
,
4555 U64_PRINTF_ARG(adj
), U64_PRINTF_ARG(chan
->global_identifier
),
4556 U64_PRINTF_ARG(estimated_total_queue_size
));
4557 /* Tell the scheduler we're increasing the queue size */
4558 scheduler_adjust_queue_size(chan
, 1, adj
);
4560 } else if (queued
< chan
->bytes_queued_for_xmit
) {
4561 adj
= chan
->bytes_queued_for_xmit
- queued
;
4562 log_debug(LD_CHANNEL
,
4563 "Decreasing queue size for channel " U64_FORMAT
" by " U64_FORMAT
4564 " from " U64_FORMAT
" to " U64_FORMAT
,
4565 U64_PRINTF_ARG(chan
->global_identifier
),
4566 U64_PRINTF_ARG(adj
),
4567 U64_PRINTF_ARG(chan
->bytes_queued_for_xmit
),
4568 U64_PRINTF_ARG(queued
));
4569 /* Update the channel's estimate */
4570 chan
->bytes_queued_for_xmit
= queued
;
4572 /* Update the global queue size estimate if appropriate */
4573 if (chan
->state
== CHANNEL_STATE_OPEN
||
4574 chan
->state
== CHANNEL_STATE_MAINT
) {
4575 estimated_total_queue_size
-= adj
;
4576 log_debug(LD_CHANNEL
,
4577 "Decreasing global queue size by " U64_FORMAT
" for channel "
4578 U64_FORMAT
", new size is " U64_FORMAT
,
4579 U64_PRINTF_ARG(adj
), U64_PRINTF_ARG(chan
->global_identifier
),
4580 U64_PRINTF_ARG(estimated_total_queue_size
));
4581 /* Tell the scheduler we're decreasing the queue size */
4582 scheduler_adjust_queue_size(chan
, -1, adj
);