Tor  0.4.5.0-alpha-dev
entrynodes.h
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1 /* Copyright (c) 2001 Matej Pfajfar.
2  * Copyright (c) 2001-2004, Roger Dingledine.
3  * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
4  * Copyright (c) 2007-2020, The Tor Project, Inc. */
5 /* See LICENSE for licensing information */
6 
7 /**
8  * \file entrynodes.h
9  * \brief Header file for circuitbuild.c.
10  **/
11 
12 #ifndef TOR_ENTRYNODES_H
13 #define TOR_ENTRYNODES_H
14 
15 #include "lib/container/handles.h"
16 
17 /* Forward declare for guard_selection_t; entrynodes.c has the real struct */
18 typedef struct guard_selection_t guard_selection_t;
19 
20 /* Forward declare for entry_guard_t; the real declaration is private. */
21 typedef struct entry_guard_t entry_guard_t;
22 
23 /* Forward declaration for circuit_guard_state_t; the real declaration is
24  private. */
25 typedef struct circuit_guard_state_t circuit_guard_state_t;
26 
27 /* Forward declaration for entry_guard_restriction_t; the real declaration is
28  private. */
29 typedef struct entry_guard_restriction_t entry_guard_restriction_t;
30 
31 /** Information about a guard's pathbias status.
32  * These fields are used in circpathbias.c to try to detect entry
33  * nodes that are failing circuits at a suspicious frequency.
34  */
35 typedef struct guard_pathbias_t {
36  unsigned int path_bias_noticed : 1; /**< Did we alert the user about path
37  * bias for this node already? */
38  unsigned int path_bias_warned : 1; /**< Did we alert the user about path bias
39  * for this node already? */
40  unsigned int path_bias_extreme : 1; /**< Did we alert the user about path
41  * bias for this node already? */
42  unsigned int path_bias_disabled : 1; /**< Have we disabled this node because
43  * of path bias issues? */
44  unsigned int path_bias_use_noticed : 1; /**< Did we alert the user about path
45  * use bias for this node already? */
46  unsigned int path_bias_use_extreme : 1; /**< Did we alert the user about path
47  * use bias for this node already? */
48 
49  double circ_attempts; /**< Number of circuits this guard has "attempted" */
50  double circ_successes; /**< Number of successfully built circuits using
51  * this guard as first hop. */
52  double successful_circuits_closed; /**< Number of circuits that carried
53  * streams successfully. */
54  double collapsed_circuits; /**< Number of fully built circuits that were
55  * remotely closed before any streams were
56  * attempted. */
57  double unusable_circuits; /**< Number of circuits for which streams were
58  * attempted, but none succeeded. */
59  double timeouts; /**< Number of 'right-censored' circuit timeouts for this
60  * guard. */
61  double use_attempts; /**< Number of circuits we tried to use with streams */
62  double use_successes; /**< Number of successfully used circuits using
63  * this guard as first hop. */
65 
66 #if defined(ENTRYNODES_PRIVATE)
68 
69 /**
70  * @name values for entry_guard_t.is_reachable.
71  *
72  * See entry_guard_t.is_reachable for more information.
73  */
74 /**@{*/
75 #define GUARD_REACHABLE_NO 0
76 #define GUARD_REACHABLE_YES 1
77 #define GUARD_REACHABLE_MAYBE 2
78 /**@}*/
79 
80 /** An entry_guard_t represents our information about a chosen long-term
81  * first hop, known as a "helper" node in the literature. We can't just
82  * use a node_t, since we want to remember these even when we
83  * don't have any directory info. */
84 struct entry_guard_t {
85  HANDLE_ENTRY(entry_guard, entry_guard_t);
86 
87  char nickname[MAX_HEX_NICKNAME_LEN+1];
88  char identity[DIGEST_LEN];
90 
91  /**
92  * @name new guard selection algorithm fields.
93  *
94  * Only the new (prop271) algorithm uses these. For a more full
95  * description of the algorithm, see the module documentation for
96  * entrynodes.c
97  */
98  /**@{*/
99 
100  /* == Persistent fields, present for all sampled guards. */
101  /** When was this guard added to the sample? */
102  time_t sampled_on_date;
103  /** Since what date has this guard been "unlisted"? A guard counts as
104  * unlisted if we have a live consensus that does not include it, or
105  * if we have a live consensus that does not include it as a usable
106  * guard. This field is zero when the guard is listed. */
107  time_t unlisted_since_date; // can be zero
108  /** What version of Tor added this guard to the sample? */
109  char *sampled_by_version;
110  /** Is this guard listed right now? If this is set, then
111  * unlisted_since_date should be set too. */
112  unsigned currently_listed : 1;
113 
114  /* == Persistent fields, for confirmed guards only */
115  /** When was this guard confirmed? (That is, when did we first use it
116  * successfully and decide to keep it?) This field is zero if this is not a
117  * confirmed guard. */
118  time_t confirmed_on_date; /* 0 if not confirmed */
119  /**
120  * In what order was this guard sampled? Guards with
121  * lower indices appear earlier on the sampled list, the confirmed list and
122  * the primary list as a result of Prop 310
123  */
124  int sampled_idx;
125 
126  /**
127  * In what order was this guard confirmed? Guards with lower indices
128  * appear earlier on the confirmed list. If the confirmed list is compacted,
129  * this field corresponds to the index of this guard on the confirmed list.
130  *
131  * This field is set to -1 if this guard is not confirmed.
132  */
133  int confirmed_idx; /* -1 if not confirmed; otherwise the order that this
134  * item should occur in the CONFIRMED_GUARDS ordered
135  * list */
136 
137  /**
138  * Which selection does this guard belong to?
139  */
140  char *selection_name;
141 
142  /** Bridges only: address of the bridge. */
143  tor_addr_port_t *bridge_addr;
144 
145  /* ==== Non-persistent fields. */
146  /* == These are used by sampled guards */
147  /** When did we last decide to try using this guard for a circuit? 0 for
148  * "not since we started up." */
149  time_t last_tried_to_connect;
150  /** How reachable do we consider this guard to be? One of
151  * GUARD_REACHABLE_NO, GUARD_REACHABLE_YES, or GUARD_REACHABLE_MAYBE. */
152  unsigned is_reachable : 2;
153  /** Boolean: true iff this guard is pending. A pending guard is one
154  * that we have an in-progress circuit through, and which we do not plan
155  * to try again until it either succeeds or fails. Primary guards can
156  * never be pending. */
157  unsigned is_pending : 1;
158  /** If true, don't write this guard to disk. (Used for bridges with unknown
159  * identities) */
160  unsigned is_persistent : 1;
161  /** When did we get the earliest connection failure for this guard?
162  * We clear this field on a successful connect. We do _not_ clear it
163  * when we mark the guard as "MAYBE" reachable.
164  */
165  time_t failing_since;
166 
167  /* == Set inclusion flags. */
168  /** If true, this guard is in the filtered set. The filtered set includes
169  * all sampled guards that our configuration allows us to use. */
170  unsigned is_filtered_guard : 1;
171  /** If true, this guard is in the usable filtered set. The usable filtered
172  * set includes all filtered guards that are not believed to be
173  * unreachable. (That is, those for which is_reachable is not
174  * GUARD_REACHABLE_NO) */
175  unsigned is_usable_filtered_guard : 1;
176  unsigned is_primary:1;
177 
178  /** This string holds any fields that we are maintaining because
179  * we saw them in the state, even if we don't understand them. */
180  char *extra_state_fields;
181 
182  /** Backpointer to the guard selection that this guard belongs to.
183  * The entry_guard_t must never outlive its guard_selection. */
184  guard_selection_t *in_selection;
185  /**@}*/
186 
187  /** Path bias information for this guard. */
188  guard_pathbias_t pb;
189 };
190 
191 /**
192  * Possible rules for a guard selection to follow
193  */
194 typedef enum guard_selection_type_t {
195  /** Infer the type of this selection from its name. */
196  GS_TYPE_INFER=0,
197  /** Use the normal guard selection algorithm, taking our sample from the
198  * complete list of guards in the consensus. */
199  GS_TYPE_NORMAL=1,
200  /** Use the normal guard selection algorithm, taking our sample from the
201  * configured bridges, and allowing it to grow as large as all the configured
202  * bridges */
203  GS_TYPE_BRIDGE,
204  /** Use the normal guard selection algorithm, taking our sample from the
205  * set of filtered nodes. */
206  GS_TYPE_RESTRICTED,
207 } guard_selection_type_t;
208 
209 /**
210  * All of the the context for guard selection on a particular client.
211  *
212  * We maintain multiple guard selection contexts for a client, depending
213  * aspects on its current configuration -- whether an extremely
214  * restrictive EntryNodes is used, whether UseBridges is enabled, and so
215  * on.)
216  *
217  * See the module documentation for entrynodes.c for more information
218  * about guard selection algorithms.
219  */
220 struct guard_selection_t {
221  /**
222  * The name for this guard-selection object. (Must not contain spaces).
223  */
224  char *name;
225 
226  /**
227  * What rules does this guard-selection object follow?
228  */
229  guard_selection_type_t type;
230 
231  /**
232  * A value of 1 means that primary_entry_guards is up-to-date with respect to
233  * the consensus and status info that we currently have; 0 means we need to
234  * recalculate it before using primary_entry_guards or the is_primary flag on
235  * any guard.
236  */
237  int primary_guards_up_to_date;
238 
239  /**
240  * A list of the sampled entry guards, as entry_guard_t structures.
241  * Not in any particular order. When we 'sample' a guard, we are
242  * noting it as a possible guard to pick in the future. The use of
243  * sampling here prevents us from being forced by an attacker to try
244  * every guard on the network. This list is persistent.
245  */
246  smartlist_t *sampled_entry_guards;
247 
248  /**
249  * Ordered list (from highest to lowest priority) of guards that we
250  * have successfully contacted and decided to use. Every member of
251  * this list is a member of sampled_entry_guards. Every member should
252  * have confirmed_on_date set.
253  * The ordering of the list should be by sampled idx. The reasoning behind
254  * it is linked to Proposal 310.
255  *
256  * This list is persistent. It is a subset of the elements in
257  * sampled_entry_guards, and its pointers point to elements of
258  * sampled_entry_guards.
259  */
260  smartlist_t *confirmed_entry_guards;
261 
262  /**
263  * Ordered list (from highest to lowest priority) of guards that we
264  * are willing to use the most happily. These guards may or may not
265  * yet be confirmed yet. If we can use one of these guards, we are
266  * probably not on a network that is trying to restrict our guard
267  * choices.
268  *
269  * This list is a subset of the elements in
270  * sampled_entry_guards, and its pointers point to elements of
271  * sampled_entry_guards.
272  */
273  smartlist_t *primary_entry_guards;
274 
275  /** When did we last successfully build a circuit or use a circuit? */
276  time_t last_time_on_internet;
277 
278  /** What confirmed_idx value should the next-added member of
279  * confirmed_entry_guards receive? */
280  int next_confirmed_idx;
281 
282  /** What sampled_idx value should the next-added member of
283  * sampled_entry_guards receive? This should follow the size of the sampled
284  * list until sampled relays get pruned for some reason
285  */
286  int next_sampled_idx;
287 
288 };
289 
290 struct entry_guard_handle_t;
291 
292 /** Types of restrictions we impose when picking guard nodes */
293 typedef enum guard_restriction_type_t {
294  /* Don't pick the same guard node as our exit node (or its family) */
295  RST_EXIT_NODE = 0,
296  /* Don't pick dirguards that have previously shown to be outdated */
297  RST_OUTDATED_MD_DIRSERVER = 1
298 } guard_restriction_type_t;
299 
300 /**
301  * A restriction to remember which entry guards are off-limits for a given
302  * circuit.
303  *
304  * Note: This mechanism is NOT for recording which guards are never to be
305  * used: only which guards cannot be used on <em>one particular circuit</em>.
306  */
307 struct entry_guard_restriction_t {
308  /* What type of restriction are we imposing? */
309  guard_restriction_type_t type;
310 
311  /* In case of restriction type RST_EXIT_NODE, the guard's RSA identity
312  * digest must not equal this; and it must not be in the same family as any
313  * node with this digest. */
314  uint8_t exclude_id[DIGEST_LEN];
315 };
316 
317 /**
318  * Per-circuit state to track whether we'll be able to use the circuit.
319  */
320 struct circuit_guard_state_t {
321  /** Handle to the entry guard object for this circuit. */
322  struct entry_guard_handle_t *guard;
323  /** The time at which <b>state</b> last changed. */
324  time_t state_set_at;
325  /** One of GUARD_CIRC_STATE_* */
326  uint8_t state;
327 
328  /**
329  * A set of restrictions that were placed on this guard when we selected it
330  * for this particular circuit. We need to remember the restrictions here,
331  * since any guard that breaks these restrictions will not block this
332  * circuit from becoming COMPLETE.
333  */
334  entry_guard_restriction_t *restrictions;
335 };
336 #endif /* defined(ENTRYNODES_PRIVATE) */
337 
338 /* Common entry points for old and new guard code */
339 int guards_update_all(void);
341  uint8_t purpose,
342  circuit_guard_state_t **guard_state_out);
343 const node_t *guards_choose_dirguard(uint8_t dir_purpose,
344  circuit_guard_state_t **guard_state_out);
345 
346 #if 1
347 /* XXXX NM I would prefer that all of this stuff be private to
348  * entrynodes.c. */
350  guard_selection_t *gs, const char *digest);
351 entry_guard_t *entry_guard_get_by_id_digest(const char *digest);
352 
353 circuit_guard_state_t *
354 get_guard_state_for_bridge_desc_fetch(const char *digest);
355 
356 void entry_guards_changed_for_guard_selection(guard_selection_t *gs);
357 void entry_guards_changed(void);
358 guard_selection_t * get_guard_selection_info(void);
359 int num_live_entry_guards_for_guard_selection(
360  guard_selection_t *gs,
361  int for_directory);
362 int num_live_entry_guards(int for_directory);
363 #endif /* 1 */
364 
365 const node_t *entry_guard_find_node(const entry_guard_t *guard);
366 const char *entry_guard_get_rsa_id_digest(const entry_guard_t *guard);
367 const char *entry_guard_describe(const entry_guard_t *guard);
368 guard_pathbias_t *entry_guard_get_pathbias_state(entry_guard_t *guard);
369 
370 /** Enum to specify how we're going to use a given guard, when we're picking
371  * one for immediate use. */
372 typedef enum {
373  GUARD_USAGE_TRAFFIC = 0,
374  GUARD_USAGE_DIRGUARD = 1
375 } guard_usage_t;
376 
377 #define circuit_guard_state_free(val) \
378  FREE_AND_NULL(circuit_guard_state_t, circuit_guard_state_free_, (val))
379 
380 void circuit_guard_state_free_(circuit_guard_state_t *state);
381 int entry_guard_pick_for_circuit(guard_selection_t *gs,
382  guard_usage_t usage,
383  entry_guard_restriction_t *rst,
384  const node_t **chosen_node_out,
385  circuit_guard_state_t **guard_state_out);
386 
387 /* We just connected to an entry guard. What should we do with the circuit? */
388 typedef enum {
389  GUARD_USABLE_NEVER = -1, /* Never use the circuit */
390  GUARD_MAYBE_USABLE_LATER = 0, /* Keep it. We might use it in the future */
391  GUARD_USABLE_NOW = 1, /* Use it right now */
392 } guard_usable_t;
393 
394 guard_usable_t entry_guard_succeeded(circuit_guard_state_t **guard_state_p);
395 void entry_guard_failed(circuit_guard_state_t **guard_state_p);
396 void entry_guard_cancel(circuit_guard_state_t **guard_state_p);
398 int entry_guards_update_all(guard_selection_t *gs);
399 int entry_guards_upgrade_waiting_circuits(guard_selection_t *gs,
400  const smartlist_t *all_circuits,
401  smartlist_t *newly_complete_out);
402 int entry_guard_state_should_expire(circuit_guard_state_t *guard_state);
403 void entry_guards_note_internet_connectivity(guard_selection_t *gs);
404 
405 int update_guard_selection_choice(const or_options_t *options);
406 
407 int entry_guard_could_succeed(const circuit_guard_state_t *guard_state);
408 
409 MOCK_DECL(int,num_bridges_usable,(int use_maybe_reachable));
410 
411 #ifdef ENTRYNODES_PRIVATE
412 /**
413  * @name Default values for the parameters for the new (prop271) entry guard
414  * algorithm.
415  */
416 /**@{*/
417 /**
418  * We never let our sampled guard set grow larger than this percentage
419  * of the guards on the network.
420  */
421 #define DFLT_MAX_SAMPLE_THRESHOLD_PERCENT 20
422 /**
423  * We never let our sampled guard set grow larger than this number of
424  * guards.
425  */
426 #define DFLT_MAX_SAMPLE_SIZE 60
427 /**
428  * We always try to make our sample contain at least this many guards.
429  */
430 #define DFLT_MIN_FILTERED_SAMPLE_SIZE 20
431 /**
432  * If a guard is unlisted for this many days in a row, we remove it.
433  */
434 #define DFLT_REMOVE_UNLISTED_GUARDS_AFTER_DAYS 20
435 /**
436  * We remove unconfirmed guards from the sample after this many days,
437  * regardless of whether they are listed or unlisted.
438  */
439 #define DFLT_GUARD_LIFETIME_DAYS 120
440 /**
441  * We remove confirmed guards from the sample if they were sampled
442  * GUARD_LIFETIME_DAYS ago and confirmed this many days ago.
443  */
444 #define DFLT_GUARD_CONFIRMED_MIN_LIFETIME_DAYS 60
445 /**
446  * How many guards do we try to keep on our primary guard list?
447  */
448 #define DFLT_N_PRIMARY_GUARDS 3
449 /**
450  * Of the live guards on the primary guard list, how many do we consider when
451  * choosing a guard to use?
452  */
453 #define DFLT_N_PRIMARY_GUARDS_TO_USE 1
454 /**
455  * As DFLT_N_PRIMARY_GUARDS, but for choosing which directory guard to use.
456  */
457 #define DFLT_N_PRIMARY_DIR_GUARDS_TO_USE 3
458 /**
459  * If we haven't successfully built or used a circuit in this long, then
460  * consider that the internet is probably down.
461  */
462 #define DFLT_INTERNET_LIKELY_DOWN_INTERVAL (10*60)
463 /**
464  * If we're trying to connect to a nonprimary guard for at least this
465  * many seconds, and we haven't gotten the connection to work, we will treat
466  * lower-priority guards as usable.
467  */
468 #define DFLT_NONPRIMARY_GUARD_CONNECT_TIMEOUT 15
469 /**
470  * If a circuit has been sitting around in 'waiting for better guard' state
471  * for at least this long, we'll expire it.
472  */
473 #define DFLT_NONPRIMARY_GUARD_IDLE_TIMEOUT (10*60)
474 /**
475  * If our configuration retains fewer than this fraction of guards from the
476  * torrc, we are in a restricted setting.
477  */
478 #define DFLT_MEANINGFUL_RESTRICTION_PERCENT 20
479 /**
480  * If our configuration retains fewer than this fraction of guards from the
481  * torrc, we are in an extremely restricted setting, and should warn.
482  */
483 #define DFLT_EXTREME_RESTRICTION_PERCENT 1
484 /**@}*/
485 
486 STATIC double get_max_sample_threshold(void);
490 STATIC int get_guard_lifetime(void);
492 STATIC int get_n_primary_guards(void);
499 
500 HANDLE_DECL(entry_guard, entry_guard_t, STATIC)
501 #define entry_guard_handle_free(h) \
502  FREE_AND_NULL(entry_guard_handle_t, entry_guard_handle_free_, (h))
503 
504 STATIC guard_selection_type_t guard_selection_infer_type(
505  guard_selection_type_t type_in,
506  const char *name);
507 STATIC guard_selection_t *guard_selection_new(const char *name,
508  guard_selection_type_t type);
509 STATIC guard_selection_t *get_guard_selection_by_name(
510  const char *name, guard_selection_type_t type, int create_if_absent);
511 STATIC void guard_selection_free_(guard_selection_t *gs);
512 #define guard_selection_free(gs) \
513  FREE_AND_NULL(guard_selection_t, guard_selection_free_, (gs))
515  (guard_selection_t *gs, const entry_guard_t *guard));
516 STATIC const char *choose_guard_selection(const or_options_t *options,
517  const networkstatus_t *ns,
518  const guard_selection_t *old_selection,
519  guard_selection_type_t *type_out);
520 STATIC entry_guard_t *get_sampled_guard_with_id(guard_selection_t *gs,
521  const uint8_t *rsa_id);
522 
523 MOCK_DECL(STATIC time_t, randomize_time, (time_t now, time_t max_backdate));
524 
525 MOCK_DECL(STATIC circuit_guard_state_t *,
526  circuit_guard_state_new,(entry_guard_t *guard, unsigned state,
527  entry_guard_restriction_t *rst));
528 
529 STATIC entry_guard_t *entry_guard_add_to_sample(guard_selection_t *gs,
530  const node_t *node);
531 STATIC entry_guard_t *entry_guards_expand_sample(guard_selection_t *gs);
532 STATIC char *entry_guard_encode_for_state(entry_guard_t *guard, int
533  dense_sampled_index);
534 STATIC entry_guard_t *entry_guard_parse_from_state(const char *s);
535 #define entry_guard_free(e) \
536  FREE_AND_NULL(entry_guard_t, entry_guard_free_, (e))
537 STATIC void entry_guard_free_(entry_guard_t *e);
538 STATIC void entry_guards_update_filtered_sets(guard_selection_t *gs);
539 STATIC int entry_guards_all_primary_guards_are_down(guard_selection_t *gs);
540 /**
541  * @name Flags for first_reachable_filtered_entry_guard()
542  */
543 /**@{*/
544 #define SAMPLE_EXCLUDE_CONFIRMED (1u<<0)
545 #define SAMPLE_EXCLUDE_PRIMARY (1u<<1)
546 #define SAMPLE_EXCLUDE_PENDING (1u<<2)
547 #define SAMPLE_NO_UPDATE_PRIMARY (1u<<3)
548 #define SAMPLE_EXCLUDE_NO_DESCRIPTOR (1u<<4)
549 /**@}*/
551  guard_selection_t *gs,
552  const entry_guard_restriction_t *rst,
553  unsigned flags);
554 STATIC void entry_guard_consider_retry(entry_guard_t *guard);
555 STATIC void make_guard_confirmed(guard_selection_t *gs, entry_guard_t *guard);
556 STATIC void entry_guards_update_confirmed(guard_selection_t *gs);
557 STATIC void entry_guards_update_primary(guard_selection_t *gs);
558 STATIC int num_reachable_filtered_guards(const guard_selection_t *gs,
559  const entry_guard_restriction_t *rst);
560 STATIC void sampled_guards_update_from_consensus(guard_selection_t *gs);
561 /**
562  * @name Possible guard-states for a circuit.
563  */
564 /**@{*/
565 /** State for a circuit that can (so far as the guard subsystem is
566  * concerned) be used for actual traffic as soon as it is successfully
567  * opened. */
568 #define GUARD_CIRC_STATE_USABLE_ON_COMPLETION 1
569 /** State for an non-open circuit that we shouldn't use for actual
570  * traffic, when it completes, unless other circuits to preferable
571  * guards fail. */
572 #define GUARD_CIRC_STATE_USABLE_IF_NO_BETTER_GUARD 2
573 /** State for an open circuit that we shouldn't use for actual traffic
574  * unless other circuits to preferable guards fail. */
575 #define GUARD_CIRC_STATE_WAITING_FOR_BETTER_GUARD 3
576 /** State for a circuit that can (so far as the guard subsystem is
577  * concerned) be used for actual traffic. */
578 #define GUARD_CIRC_STATE_COMPLETE 4
579 /** State for a circuit that is unusable, and will not become usable. */
580 #define GUARD_CIRC_STATE_DEAD 5
581 /**@}*/
582 STATIC void entry_guards_note_guard_failure(guard_selection_t *gs,
583  entry_guard_t *guard);
584 STATIC entry_guard_t *select_entry_guard_for_circuit(guard_selection_t *gs,
585  guard_usage_t usage,
586  const entry_guard_restriction_t *rst,
587  unsigned *state_out);
588 STATIC void mark_primary_guards_maybe_reachable(guard_selection_t *gs);
589 STATIC unsigned entry_guards_note_guard_success(guard_selection_t *gs,
590  entry_guard_t *guard,
591  unsigned old_state);
592 STATIC int entry_guard_has_higher_priority(entry_guard_t *a, entry_guard_t *b);
593 STATIC char *getinfo_helper_format_single_entry_guard(const entry_guard_t *e);
594 
595 STATIC entry_guard_restriction_t *guard_create_exit_restriction(
596  const uint8_t *exit_id);
597 
598 STATIC entry_guard_restriction_t *guard_create_dirserver_md_restriction(void);
599 
600 STATIC void entry_guard_restriction_free_(entry_guard_restriction_t *rst);
601 #define entry_guard_restriction_free(rst) \
602  FREE_AND_NULL(entry_guard_restriction_t, \
603  entry_guard_restriction_free_, (rst))
604 
605 #endif /* defined(ENTRYNODES_PRIVATE) */
606 
607 void remove_all_entry_guards_for_guard_selection(guard_selection_t *gs);
608 void remove_all_entry_guards(void);
609 
610 struct bridge_info_t;
612  const uint8_t *rsa_id_digest);
613 
614 int entry_list_is_constrained(const or_options_t *options);
615 int guards_retry_optimistic(const or_options_t *options);
616 int entry_guards_parse_state_for_guard_selection(
617  guard_selection_t *gs, or_state_t *state, int set, char **msg);
618 int entry_guards_parse_state(or_state_t *state, int set, char **msg);
621  const char *question, char **answer,
622  const char **errmsg);
623 
624 int entries_known_but_down(const or_options_t *options);
625 void entries_retry_all(const or_options_t *options);
626 
628  int num_present, int num_usable);
629 char *guard_selection_get_err_str_if_dir_info_missing(guard_selection_t *gs,
630  int using_mds,
631  int num_present, int num_usable);
632 
633 void entry_guards_free_all(void);
634 
635 double pathbias_get_close_success_count(entry_guard_t *guard);
636 double pathbias_get_use_success_count(entry_guard_t *guard);
637 
638 /** Contains the bandwidth of a relay as a guard and as a non-guard
639  * after the guardfraction has been considered. */
641  /** Bandwidth as a guard after guardfraction has been considered. */
642  int guard_bw;
643  /** Bandwidth as a non-guard after guardfraction has been considered. */
646 
648 
649 void
650 guard_get_guardfraction_bandwidth(guardfraction_bandwidth_t *guardfraction_bw,
651  int orig_bandwidth,
652  uint32_t guardfraction_percentage);
653 
654 #endif /* !defined(TOR_ENTRYNODES_H) */
entry_guard_get_by_id_digest
entry_guard_t * entry_guard_get_by_id_digest(const char *digest)
Definition: entrynodes.c:3341
entry_guard_state_should_expire
int entry_guard_state_should_expire(circuit_guard_state_t *guard_state)
Definition: entrynodes.c:2802
circuit_guard_state_new
STATIC circuit_guard_state_t * circuit_guard_state_new(entry_guard_t *guard, unsigned state, entry_guard_restriction_t *rst)
Definition: entrynodes.c:2416
num_bridges_usable
int num_bridges_usable(int use_maybe_reachable)
Definition: entrynodes.c:3412
guardfraction_bandwidth_t::non_guard_bw
int non_guard_bw
Definition: entrynodes.h:644
get_nonprimary_guard_idle_timeout
STATIC int get_nonprimary_guard_idle_timeout(void)
Definition: entrynodes.c:532
entry_guards_update_confirmed
STATIC void entry_guards_update_confirmed(guard_selection_t *gs)
Definition: entrynodes.c:1836
circuit_guard_state_free_
void circuit_guard_state_free_(circuit_guard_state_t *state)
Definition: entrynodes.c:2403
or_state_t
Definition: or_state_st.h:21
get_max_sample_size_absolute
STATIC int get_max_sample_size_absolute(void)
Definition: entrynodes.c:388
entry_guards_note_guard_success
STATIC unsigned entry_guards_note_guard_success(guard_selection_t *gs, entry_guard_t *guard, unsigned old_state)
Definition: entrynodes.c:2285
name
const char * name
Definition: config.c:2441
entry_guard_cancel
void entry_guard_cancel(circuit_guard_state_t **guard_state_p)
Definition: entrynodes.c:2513
get_sampled_guard_with_id
STATIC entry_guard_t * get_sampled_guard_with_id(guard_selection_t *gs, const uint8_t *rsa_id)
Definition: entrynodes.c:784
guard_pathbias_t::path_bias_extreme
unsigned int path_bias_extreme
Definition: entrynodes.h:40
get_n_primary_guards
STATIC int get_n_primary_guards(void)
Definition: entrynodes.c:460
guard_pathbias_t::unusable_circuits
double unusable_circuits
Definition: entrynodes.h:57
guard_pathbias_t::circ_attempts
double circ_attempts
Definition: entrynodes.h:49
entry_guard_add_to_sample
STATIC entry_guard_t * entry_guard_add_to_sample(guard_selection_t *gs, const node_t *node)
Definition: entrynodes.c:847
entry_guards_update_filtered_sets
STATIC void entry_guards_update_filtered_sets(guard_selection_t *gs)
Definition: entrynodes.c:1710
getinfo_helper_entry_guards
int getinfo_helper_entry_guards(control_connection_t *conn, const char *question, char **answer, const char **errmsg)
Definition: entrynodes.c:3657
entry_guard_consider_retry
STATIC void entry_guard_consider_retry(entry_guard_t *guard)
Definition: entrynodes.c:2039
entry_guard_get_by_id_digest_for_guard_selection
entry_guard_t * entry_guard_get_by_id_digest_for_guard_selection(guard_selection_t *gs, const char *digest)
Definition: entrynodes.c:3322
get_nonprimary_guard_connect_timeout
STATIC int get_nonprimary_guard_connect_timeout(void)
Definition: entrynodes.c:520
mark_primary_guards_maybe_reachable
STATIC void mark_primary_guards_maybe_reachable(guard_selection_t *gs)
Definition: entrynodes.c:587
guard_pathbias_t::path_bias_use_noticed
unsigned int path_bias_use_noticed
Definition: entrynodes.h:44
entry_guard_encode_for_state
STATIC char * entry_guard_encode_for_state(entry_guard_t *guard, int dense_sampled_idx)
Definition: entrynodes.c:2833
entry_guard_describe
const char * entry_guard_describe(const entry_guard_t *guard)
Definition: entrynodes.c:319
guards_retry_optimistic
int guards_retry_optimistic(const or_options_t *options)
Definition: entrynodes.c:3839
get_guard_confirmed_min_lifetime
STATIC int get_guard_confirmed_min_lifetime(void)
Definition: entrynodes.c:446
entry_guard_failed
void entry_guard_failed(circuit_guard_state_t **guard_state_p)
Definition: entrynodes.c:2534
entry_guard_succeeded
guard_usable_t entry_guard_succeeded(circuit_guard_state_t **guard_state_p)
Definition: entrynodes.c:2486
entry_guards_note_internet_connectivity
void entry_guards_note_internet_connectivity(guard_selection_t *gs)
Definition: entrynodes.c:2070
guard_pathbias_t::path_bias_disabled
unsigned int path_bias_disabled
Definition: entrynodes.h:42
guard_pathbias_t::collapsed_circuits
double collapsed_circuits
Definition: entrynodes.h:54
entry_guards_parse_state
int entry_guards_parse_state(or_state_t *state, int set, char **msg)
Definition: entrynodes.c:3497
get_min_filtered_sample_size
STATIC int get_min_filtered_sample_size(void)
Definition: entrynodes.c:398
guard_pathbias_t::path_bias_noticed
unsigned int path_bias_noticed
Definition: entrynodes.h:36
guard_pathbias_t
Definition: entrynodes.h:35
guard_create_dirserver_md_restriction
STATIC entry_guard_restriction_t * guard_create_dirserver_md_restriction(void)
Definition: entrynodes.c:1605
guard_usage_t
guard_usage_t
Definition: entrynodes.h:372
update_guard_selection_choice
int update_guard_selection_choice(const or_options_t *options)
Definition: entrynodes.c:725
guard_pathbias_t::successful_circuits_closed
double successful_circuits_closed
Definition: entrynodes.h:52
DIGEST_LEN
#define DIGEST_LEN
Definition: digest_sizes.h:20
should_apply_guardfraction
int should_apply_guardfraction(const networkstatus_t *ns)
Definition: entrynodes.c:184
guards_update_all
int guards_update_all(void)
Definition: entrynodes.c:3727
get_guard_lifetime
STATIC int get_guard_lifetime(void)
Definition: entrynodes.c:431
get_remove_unlisted_guards_after_days
STATIC int get_remove_unlisted_guards_after_days(void)
Definition: entrynodes.c:408
get_meaningful_restriction_threshold
STATIC double get_meaningful_restriction_threshold(void)
Definition: entrynodes.c:544
pathbias_get_close_success_count
double pathbias_get_close_success_count(entry_guard_t *guard)
Definition: circpathbias.c:1297
get_max_sample_threshold
STATIC double get_max_sample_threshold(void)
Definition: entrynodes.c:376
guardfraction_bandwidth_t
Definition: entrynodes.h:640
entry_guards_update_state
void entry_guards_update_state(or_state_t *state)
Definition: entrynodes.c:3559
entry_guard_free_
STATIC void entry_guard_free_(entry_guard_t *e)
Definition: entrynodes.c:3375
tor_addr_port_t
Definition: address.h:80
entry_guards_upgrade_waiting_circuits
int entry_guards_upgrade_waiting_circuits(guard_selection_t *gs, const smartlist_t *all_circuits, smartlist_t *newly_complete_out)
Definition: entrynodes.c:2638
node_t
Definition: node_st.h:34
first_reachable_filtered_entry_guard
STATIC entry_guard_t * first_reachable_filtered_entry_guard(guard_selection_t *gs, const entry_guard_restriction_t *rst, unsigned flags)
Definition: entrynodes.c:1731
select_entry_guard_for_circuit
STATIC entry_guard_t * select_entry_guard_for_circuit(guard_selection_t *gs, guard_usage_t usage, const entry_guard_restriction_t *rst, unsigned *state_out)
Definition: entrynodes.c:2210
make_guard_confirmed
STATIC void make_guard_confirmed(guard_selection_t *gs, entry_guard_t *guard)
Definition: entrynodes.c:1868
randomize_time
STATIC time_t randomize_time(time_t now, time_t max_backdate)
Definition: entrynodes.c:350
entry_guard_could_succeed
int entry_guard_could_succeed(const circuit_guard_state_t *guard_state)
Definition: entrynodes.c:3575
guard_pathbias_t::use_successes
double use_successes
Definition: entrynodes.h:62
ed25519_public_key_t
Definition: crypto_ed25519.h:23
guards_choose_guard
const node_t * guards_choose_guard(cpath_build_state_t *state, uint8_t purpose, circuit_guard_state_t **guard_state_out)
Definition: entrynodes.c:3744
entry_guard_chan_failed
void entry_guard_chan_failed(channel_t *chan)
Definition: entrynodes.c:2554
remove_all_entry_guards_for_guard_selection
void remove_all_entry_guards_for_guard_selection(guard_selection_t *gs)
Definition: entrynodes.c:3777
guard_pathbias_t::path_bias_use_extreme
unsigned int path_bias_use_extreme
Definition: entrynodes.h:46
entry_list_is_constrained
int entry_list_is_constrained(const or_options_t *options)
Definition: entrynodes.c:3392
handles.h
Macros for C weak-handle implementation.
pathbias_get_use_success_count
double pathbias_get_use_success_count(entry_guard_t *guard)
Definition: circpathbias.c:1315
MOCK_DECL
#define MOCK_DECL(rv, funcname, arglist)
Definition: testsupport.h:127
channel_t
Definition: channel.h:181
guardfraction_bandwidth_t::guard_bw
int guard_bw
Definition: entrynodes.h:642
get_guard_state_for_bridge_desc_fetch
circuit_guard_state_t * get_guard_state_for_bridge_desc_fetch(const char *digest)
Definition: entrynodes.c:3350
entry_guards_note_guard_failure
STATIC void entry_guards_note_guard_failure(guard_selection_t *gs, entry_guard_t *guard)
Definition: entrynodes.c:2255
sampled_guards_update_from_consensus
STATIC void sampled_guards_update_from_consensus(guard_selection_t *gs)
Definition: entrynodes.c:1410
guard_pathbias_t::circ_successes
double circ_successes
Definition: entrynodes.h:50
entry_guard_has_higher_priority
STATIC int entry_guard_has_higher_priority(entry_guard_t *a, entry_guard_t *b)
Definition: entrynodes.c:2356
get_guard_selection_by_name
STATIC guard_selection_t * get_guard_selection_by_name(const char *name, guard_selection_type_t type, int create_if_absent)
Definition: entrynodes.c:258
entry_guard_restriction_free_
STATIC void entry_guard_restriction_free_(entry_guard_restriction_t *rst)
Definition: entrynodes.c:2394
entry_guards_update_all
int entry_guards_update_all(guard_selection_t *gs)
Definition: entrynodes.c:2817
bridge_info_t
Definition: bridges.c:43
guard_selection_get_err_str_if_dir_info_missing
char * guard_selection_get_err_str_if_dir_info_missing(guard_selection_t *gs, int using_mds, int num_present, int num_usable)
Definition: entrynodes.c:3856
choose_guard_selection
const STATIC char * choose_guard_selection(const or_options_t *options, const networkstatus_t *live_ns, const guard_selection_t *old_selection, guard_selection_type_t *type_out)
Definition: entrynodes.c:619
entry_guards_free_all
void entry_guards_free_all(void)
Definition: entrynodes.c:3936
entry_guards_changed
void entry_guards_changed(void)
Definition: entrynodes.c:3548
entry_guard_is_listed
STATIC int entry_guard_is_listed(guard_selection_t *gs, const entry_guard_t *guard)
Definition: entrynodes.c:1255
get_n_primary_guards_to_use
STATIC int get_n_primary_guards_to_use(guard_usage_t usage)
Definition: entrynodes.c:480
entry_guard_pick_for_circuit
int entry_guard_pick_for_circuit(guard_selection_t *gs, guard_usage_t usage, entry_guard_restriction_t *rst, const node_t **chosen_node_out, circuit_guard_state_t **guard_state_out)
Definition: entrynodes.c:2440
entry_guards_changed_for_guard_selection
void entry_guards_changed_for_guard_selection(guard_selection_t *gs)
Definition: entrynodes.c:3524
guard_selection_new
STATIC guard_selection_t * guard_selection_new(const char *name, guard_selection_type_t type)
Definition: entrynodes.c:235
control_connection_t
Definition: control_connection_st.h:19
entry_guard_get_rsa_id_digest
const char * entry_guard_get_rsa_id_digest(const entry_guard_t *guard)
Definition: entrynodes.c:331
get_guard_selection_info
guard_selection_t * get_guard_selection_info(void)
Definition: entrynodes.c:307
get_extreme_restriction_threshold
STATIC double get_extreme_restriction_threshold(void)
Definition: entrynodes.c:557
guards_choose_dirguard
const node_t * guards_choose_dirguard(uint8_t dir_purpose, circuit_guard_state_t **guard_state_out)
Definition: entrynodes.c:3813
entry_guards_expand_sample
STATIC entry_guard_t * entry_guards_expand_sample(guard_selection_t *gs)
Definition: entrynodes.c:1161
guard_selection_free_
STATIC void guard_selection_free_(guard_selection_t *gs)
Definition: entrynodes.c:3914
entry_guards_update_primary
STATIC void entry_guards_update_primary(guard_selection_t *gs)
Definition: entrynodes.c:1901
cpath_build_state_t
Definition: cpath_build_state_st.h:16
MAX_HEX_NICKNAME_LEN
#define MAX_HEX_NICKNAME_LEN
Definition: or.h:115
entry_guards_get_err_str_if_dir_info_missing
char * entry_guards_get_err_str_if_dir_info_missing(int using_mds, int num_present, int num_usable)
Definition: entrynodes.c:3903
entry_guard_find_node
const node_t * entry_guard_find_node(const entry_guard_t *guard)
Definition: entrynodes.c:3331
get_internet_likely_down_interval
STATIC int get_internet_likely_down_interval(void)
Definition: entrynodes.c:508
entry_guard_get_pathbias_state
guard_pathbias_t * entry_guard_get_pathbias_state(entry_guard_t *guard)
Definition: entrynodes.c:338
guard_pathbias_t::use_attempts
double use_attempts
Definition: entrynodes.h:61
guard_pathbias_t::path_bias_warned
unsigned int path_bias_warned
Definition: entrynodes.h:38
or_options_t
Definition: or_options_st.h:39
remove_all_entry_guards
void remove_all_entry_guards(void)
Definition: entrynodes.c:3806
STATIC
#define STATIC
Definition: testsupport.h:32
getinfo_helper_format_single_entry_guard
STATIC char * getinfo_helper_format_single_entry_guard(const entry_guard_t *e)
Definition: entrynodes.c:3600
guard_pathbias_t::timeouts
double timeouts
Definition: entrynodes.h:59
networkstatus_t
Definition: networkstatus_st.h:26
num_reachable_filtered_guards
STATIC int num_reachable_filtered_guards(const guard_selection_t *gs, const entry_guard_restriction_t *rst)
Definition: entrynodes.c:1009
crypto_ed25519.h
Header for crypto_ed25519.c.
entry_guards_all_primary_guards_are_down
STATIC int entry_guards_all_primary_guards_are_down(guard_selection_t *gs)
Definition: entrynodes.c:2580
smartlist_t
Definition: smartlist_core.h:26
entry_guard_learned_bridge_identity
void entry_guard_learned_bridge_identity(const tor_addr_port_t *addrport, const uint8_t *rsa_id_digest)
Definition: entrynodes.c:960
entry_guard_parse_from_state
STATIC entry_guard_t * entry_guard_parse_from_state(const char *s)
Definition: entrynodes.c:2996
guard_selection_infer_type
STATIC guard_selection_type_t guard_selection_infer_type(guard_selection_type_t type, const char *name)
Definition: entrynodes.c:217