tor/src/or/rendcache.h
2015-10-21 10:54:07 -04:00

116 lines
4.7 KiB
C

/* Copyright (c) 2015, The Tor Project, Inc. */
/* See LICENSE for licensing information */
/**
* \file rendcache.h
* \brief Header file for rendcache.c
**/
#ifndef TOR_RENDCACHE_H
#define TOR_RENDCACHE_H
#include "or.h"
#include "rendcommon.h"
/** How old do we let hidden service descriptors get before discarding
* them as too old? */
#define REND_CACHE_MAX_AGE (2*24*60*60)
/** How wrong do we assume our clock may be when checking whether hidden
* services are too old or too new? */
#define REND_CACHE_MAX_SKEW (24*60*60)
/** How old do we keep an intro point failure entry in the failure cache? */
#define REND_CACHE_FAILURE_MAX_AGE (5*60)
/* Do not allow more than this many introduction points in a hidden service
* descriptor */
#define MAX_INTRO_POINTS 10
/** A cached rendezvous descriptor. */
typedef struct rend_cache_entry_t {
size_t len; /**< Length of <b>desc</b> */
time_t last_served; /**< When did we last write this one to somebody?
* (HSDir only) */
char *desc; /**< Service descriptor */
rend_service_descriptor_t *parsed; /**< Parsed value of 'desc' */
} rend_cache_entry_t;
/* Introduction point failure type. */
typedef struct rend_cache_failure_intro_t {
/* When this intro point failure occured thus we allocated this object and
* cache it. */
time_t created_ts;
rend_intro_point_failure_t failure_type;
} rend_cache_failure_intro_t;
/** Cache failure object indexed by service ID. */
typedef struct rend_cache_failure_t {
/* Contains rend_cache_failure_intro_t indexed by identity digest. */
digestmap_t *intro_failures;
} rend_cache_failure_t;
typedef enum {
REND_CACHE_TYPE_CLIENT = 1,
REND_CACHE_TYPE_SERVICE = 2,
} rend_cache_type_t;
void rend_cache_init(void);
void rend_cache_clean(time_t now, rend_cache_type_t cache_type);
void rend_cache_failure_clean(time_t now);
void rend_cache_clean_v2_descs_as_dir(time_t now, size_t min_to_remove);
void rend_cache_purge(void);
void rend_cache_free_all(void);
int rend_cache_lookup_entry(const char *query, int version,
rend_cache_entry_t **entry_out);
int rend_cache_lookup_v2_desc_as_service(const char *query,
rend_cache_entry_t **entry_out);
int rend_cache_lookup_v2_desc_as_dir(const char *query, const char **desc);
/** Return value from rend_cache_store_v2_desc_as_{dir,client}. */
typedef enum {
RCS_NOTDIR = -2, /**< We're not a directory */
RCS_BADDESC = -1, /**< This descriptor is no good. */
RCS_OKAY = 0 /**< All worked as expected */
} rend_cache_store_status_t;
rend_cache_store_status_t rend_cache_store_v2_desc_as_dir(const char *desc);
rend_cache_store_status_t rend_cache_store_v2_desc_as_service(
const char *desc);
rend_cache_store_status_t rend_cache_store_v2_desc_as_client(const char *desc,
const char *desc_id_base32,
const rend_data_t *rend_query,
rend_cache_entry_t **entry);
size_t rend_cache_get_total_allocation(void);
void rend_cache_intro_failure_note(rend_intro_point_failure_t failure,
const uint8_t *identity,
const char *service_id);
void rend_cache_failure_purge(void);
#ifdef RENDCACHE_PRIVATE
STATIC size_t rend_cache_entry_allocation(const rend_cache_entry_t *e);
STATIC void rend_cache_entry_free(rend_cache_entry_t *e);
STATIC void rend_cache_failure_intro_entry_free(rend_cache_failure_intro_t
*entry);
STATIC void rend_cache_failure_entry_free(rend_cache_failure_t *entry);
STATIC int cache_failure_intro_lookup(const uint8_t *identity,
const char *service_id,
rend_cache_failure_intro_t
**intro_entry);
STATIC void rend_cache_decrement_allocation(size_t n);
STATIC void rend_cache_increment_allocation(size_t n);
STATIC rend_cache_failure_intro_t *rend_cache_failure_intro_entry_new(
rend_intro_point_failure_t failure);
STATIC rend_cache_failure_t *rend_cache_failure_entry_new(void);
STATIC void rend_cache_failure_remove(rend_service_descriptor_t *desc);
STATIC void cache_failure_intro_add(const uint8_t *identity,
const char *service_id,
rend_intro_point_failure_t failure);
STATIC void validate_intro_point_failure(const rend_service_descriptor_t *desc,
const char *service_id);
STATIC void rend_cache_failure_entry_free_(void *entry);
#endif
#endif /* TOR_RENDCACHE_H */