prop224: Move some rendclient.c code to hs_common.c

Specifically move the pick_hsdir() function and all the HSDir request tracking
code. We plan to use all that code both for v2 and v3.

This commit only moves code.

Signed-off-by: David Goulet <dgoulet@torproject.org>
This commit is contained in:
George Kadianakis 2017-06-01 13:48:03 +03:00 committed by David Goulet
parent 7aef3ec0fd
commit 912c11761c
4 changed files with 235 additions and 225 deletions

View File

@ -22,6 +22,7 @@
#include "rendcommon.h"
#include "rendservice.h"
#include "router.h"
#include "routerset.h"
#include "shared_random.h"
#include "shared_random_state.h"
@ -1320,6 +1321,229 @@ hs_get_responsible_hsdirs(const ed25519_public_key_t *blinded_pk,
smartlist_free(sorted_nodes);
}
/*********************** HSDir request tracking ***************************/
/** Return the period for which a hidden service directory cannot be queried
* for the same descriptor ID again, taking TestingTorNetwork into account. */
static time_t
hsdir_requery_period(const or_options_t *options)
{
tor_assert(options);
if (options->TestingTorNetwork) {
return REND_HID_SERV_DIR_REQUERY_PERIOD_TESTING;
} else {
return REND_HID_SERV_DIR_REQUERY_PERIOD;
}
}
/** Contains the last request times to hidden service directories for
* certain queries; each key is a string consisting of the
* concatenation of a base32-encoded HS directory identity digest and
* base32-encoded HS descriptor ID; each value is a pointer to a time_t
* holding the time of the last request for that descriptor ID to that
* HS directory. */
static strmap_t *last_hid_serv_requests_ = NULL;
/** Returns last_hid_serv_requests_, initializing it to a new strmap if
* necessary. */
static strmap_t *
get_last_hid_serv_requests(void)
{
if (!last_hid_serv_requests_)
last_hid_serv_requests_ = strmap_new();
return last_hid_serv_requests_;
}
#define LAST_HID_SERV_REQUEST_KEY_LEN (REND_DESC_ID_V2_LEN_BASE32 + \
REND_DESC_ID_V2_LEN_BASE32)
/** Look up the last request time to hidden service directory <b>hs_dir</b>
* for descriptor ID <b>desc_id_base32</b>. If <b>set</b> is non-zero,
* assign the current time <b>now</b> and return that. Otherwise, return the
* most recent request time, or 0 if no such request has been sent before.
*/
static time_t
lookup_last_hid_serv_request(routerstatus_t *hs_dir,
const char *desc_id_base32,
time_t now, int set)
{
char hsdir_id_base32[REND_DESC_ID_V2_LEN_BASE32 + 1];
char hsdir_desc_comb_id[LAST_HID_SERV_REQUEST_KEY_LEN + 1];
time_t *last_request_ptr;
strmap_t *last_hid_serv_requests = get_last_hid_serv_requests();
base32_encode(hsdir_id_base32, sizeof(hsdir_id_base32),
hs_dir->identity_digest, DIGEST_LEN);
tor_snprintf(hsdir_desc_comb_id, sizeof(hsdir_desc_comb_id), "%s%s",
hsdir_id_base32,
desc_id_base32);
/* XXX++?? tor_assert(strlen(hsdir_desc_comb_id) ==
LAST_HID_SERV_REQUEST_KEY_LEN); */
if (set) {
time_t *oldptr;
last_request_ptr = tor_malloc_zero(sizeof(time_t));
*last_request_ptr = now;
oldptr = strmap_set(last_hid_serv_requests, hsdir_desc_comb_id,
last_request_ptr);
tor_free(oldptr);
} else
last_request_ptr = strmap_get_lc(last_hid_serv_requests,
hsdir_desc_comb_id);
return (last_request_ptr) ? *last_request_ptr : 0;
}
/** Clean the history of request times to hidden service directories, so that
* it does not contain requests older than REND_HID_SERV_DIR_REQUERY_PERIOD
* seconds any more. */
static void
directory_clean_last_hid_serv_requests(time_t now)
{
strmap_iter_t *iter;
time_t cutoff = now - hsdir_requery_period(get_options());
strmap_t *last_hid_serv_requests = get_last_hid_serv_requests();
for (iter = strmap_iter_init(last_hid_serv_requests);
!strmap_iter_done(iter); ) {
const char *key;
void *val;
time_t *ent;
strmap_iter_get(iter, &key, &val);
ent = (time_t *) val;
if (*ent < cutoff) {
iter = strmap_iter_next_rmv(last_hid_serv_requests, iter);
tor_free(ent);
} else {
iter = strmap_iter_next(last_hid_serv_requests, iter);
}
}
}
/** Remove all requests related to the descriptor ID <b>desc_id</b> from the
* history of times of requests to hidden service directories.
* <b>desc_id</b> is an unencoded descriptor ID of size DIGEST_LEN.
*
* This is called from rend_client_note_connection_attempt_ended(), which
* must be idempotent, so any future changes to this function must leave it
* idempotent too. */
void
purge_hid_serv_from_last_hid_serv_requests(const char *desc_id)
{
strmap_iter_t *iter;
strmap_t *last_hid_serv_requests = get_last_hid_serv_requests();
char desc_id_base32[REND_DESC_ID_V2_LEN_BASE32 + 1];
/* Key is stored with the base32 encoded desc_id. */
base32_encode(desc_id_base32, sizeof(desc_id_base32), desc_id,
DIGEST_LEN);
for (iter = strmap_iter_init(last_hid_serv_requests);
!strmap_iter_done(iter); ) {
const char *key;
void *val;
strmap_iter_get(iter, &key, &val);
/* XXX++?? tor_assert(strlen(key) == LAST_HID_SERV_REQUEST_KEY_LEN); */
if (tor_memeq(key + LAST_HID_SERV_REQUEST_KEY_LEN -
REND_DESC_ID_V2_LEN_BASE32,
desc_id_base32,
REND_DESC_ID_V2_LEN_BASE32)) {
iter = strmap_iter_next_rmv(last_hid_serv_requests, iter);
tor_free(val);
} else {
iter = strmap_iter_next(last_hid_serv_requests, iter);
}
}
}
/** Purge the history of request times to hidden service directories,
* so that future lookups of an HS descriptor will not fail because we
* accessed all of the HSDir relays responsible for the descriptor
* recently. */
void
rend_client_purge_last_hid_serv_requests(void)
{
/* Don't create the table if it doesn't exist yet (and it may very
* well not exist if the user hasn't accessed any HSes)... */
strmap_t *old_last_hid_serv_requests = last_hid_serv_requests_;
/* ... and let get_last_hid_serv_requests re-create it for us if
* necessary. */
last_hid_serv_requests_ = NULL;
if (old_last_hid_serv_requests != NULL) {
log_info(LD_REND, "Purging client last-HS-desc-request-time table");
strmap_free(old_last_hid_serv_requests, tor_free_);
}
}
/***********************************************************************/
/** This returns a good valid hs dir that should be used for the given
* descriptor id.
*
* Return NULL on error else the hsdir node pointer. */
routerstatus_t *
pick_hsdir(const char *desc_id, const char *desc_id_base32)
{
smartlist_t *responsible_dirs = smartlist_new();
smartlist_t *usable_responsible_dirs = smartlist_new();
const or_options_t *options = get_options();
routerstatus_t *hs_dir;
time_t now = time(NULL);
int excluded_some;
tor_assert(desc_id);
tor_assert(desc_id_base32);
/* Determine responsible dirs. Even if we can't get all we want, work with
* the ones we have. If it's empty, we'll notice below. */
hid_serv_get_responsible_directories(responsible_dirs, desc_id);
/* Clean request history first. */
directory_clean_last_hid_serv_requests(now);
/* Only select those hidden service directories to which we did not send a
* request recently and for which we have a router descriptor here. */
SMARTLIST_FOREACH_BEGIN(responsible_dirs, routerstatus_t *, dir) {
time_t last = lookup_last_hid_serv_request(dir, desc_id_base32,
0, 0);
const node_t *node = node_get_by_id(dir->identity_digest);
if (last + hsdir_requery_period(options) >= now ||
!node || !node_has_descriptor(node)) {
SMARTLIST_DEL_CURRENT(responsible_dirs, dir);
continue;
}
if (!routerset_contains_node(options->ExcludeNodes, node)) {
smartlist_add(usable_responsible_dirs, dir);
}
} SMARTLIST_FOREACH_END(dir);
excluded_some =
smartlist_len(usable_responsible_dirs) < smartlist_len(responsible_dirs);
hs_dir = smartlist_choose(usable_responsible_dirs);
if (!hs_dir && !options->StrictNodes) {
hs_dir = smartlist_choose(responsible_dirs);
}
smartlist_free(responsible_dirs);
smartlist_free(usable_responsible_dirs);
if (!hs_dir) {
log_info(LD_REND, "Could not pick one of the responsible hidden "
"service directories, because we requested them all "
"recently without success.");
if (options->StrictNodes && excluded_some) {
log_warn(LD_REND, "Could not pick a hidden service directory for the "
"requested hidden service: they are all either down or "
"excluded, and StrictNodes is set.");
}
} else {
/* Remember that we are requesting a descriptor from this hidden service
* directory now. */
lookup_last_hid_serv_request(hs_dir, desc_id_base32, now, 1);
}
return hs_dir;
}
/***********************************************************************/
/* Initialize the entire HS subsytem. This is called in tor_init() before any
* torrc options are loaded. Only for >= v3. */
void

View File

@ -187,6 +187,10 @@ const char *rend_data_get_desc_id(const rend_data_t *rend_data,
const uint8_t *rend_data_get_pk_digest(const rend_data_t *rend_data,
size_t *len_out);
void rend_client_purge_last_hid_serv_requests(void);
void purge_hid_serv_from_last_hid_serv_requests(const char *desc_id);
routerstatus_t *pick_hsdir(const char *desc_id, const char *desc_id_base32);
void hs_get_subcredential(const ed25519_public_key_t *identity_pk,
const ed25519_public_key_t *blinded_pk,
uint8_t *subcred_out);
@ -229,6 +233,13 @@ void hs_dec_rdv_stream_counter(origin_circuit_t *circ);
STATIC void get_disaster_srv(uint64_t time_period_num, uint8_t *srv_out);
/** The period for which a hidden service directory cannot be queried for
* the same descriptor ID again. */
#define REND_HID_SERV_DIR_REQUERY_PERIOD (15 * 60)
/** Test networks generate a new consensus every 5 or 10 seconds.
* So allow them to requery HSDirs much faster. */
#define REND_HID_SERV_DIR_REQUERY_PERIOD_TESTING (5)
#ifdef TOR_UNIT_TESTS
STATIC uint64_t get_time_period_length(void);

View File

@ -465,230 +465,6 @@ rend_client_introduction_acked(origin_circuit_t *circ,
return 0;
}
/** The period for which a hidden service directory cannot be queried for
* the same descriptor ID again. */
#define REND_HID_SERV_DIR_REQUERY_PERIOD (15 * 60)
/** Test networks generate a new consensus every 5 or 10 seconds.
* So allow them to requery HSDirs much faster. */
#define REND_HID_SERV_DIR_REQUERY_PERIOD_TESTING (5)
/** Return the period for which a hidden service directory cannot be queried
* for the same descriptor ID again, taking TestingTorNetwork into account. */
static time_t
hsdir_requery_period(const or_options_t *options)
{
tor_assert(options);
if (options->TestingTorNetwork) {
return REND_HID_SERV_DIR_REQUERY_PERIOD_TESTING;
} else {
return REND_HID_SERV_DIR_REQUERY_PERIOD;
}
}
/** Contains the last request times to hidden service directories for
* certain queries; each key is a string consisting of the
* concatenation of a base32-encoded HS directory identity digest and
* base32-encoded HS descriptor ID; each value is a pointer to a time_t
* holding the time of the last request for that descriptor ID to that
* HS directory. */
static strmap_t *last_hid_serv_requests_ = NULL;
/** Returns last_hid_serv_requests_, initializing it to a new strmap if
* necessary. */
static strmap_t *
get_last_hid_serv_requests(void)
{
if (!last_hid_serv_requests_)
last_hid_serv_requests_ = strmap_new();
return last_hid_serv_requests_;
}
#define LAST_HID_SERV_REQUEST_KEY_LEN (REND_DESC_ID_V2_LEN_BASE32 + \
REND_DESC_ID_V2_LEN_BASE32)
/** Look up the last request time to hidden service directory <b>hs_dir</b>
* for descriptor ID <b>desc_id_base32</b>. If <b>set</b> is non-zero,
* assign the current time <b>now</b> and return that. Otherwise, return the
* most recent request time, or 0 if no such request has been sent before.
*/
static time_t
lookup_last_hid_serv_request(routerstatus_t *hs_dir,
const char *desc_id_base32,
time_t now, int set)
{
char hsdir_id_base32[REND_DESC_ID_V2_LEN_BASE32 + 1];
char hsdir_desc_comb_id[LAST_HID_SERV_REQUEST_KEY_LEN + 1];
time_t *last_request_ptr;
strmap_t *last_hid_serv_requests = get_last_hid_serv_requests();
base32_encode(hsdir_id_base32, sizeof(hsdir_id_base32),
hs_dir->identity_digest, DIGEST_LEN);
tor_snprintf(hsdir_desc_comb_id, sizeof(hsdir_desc_comb_id), "%s%s",
hsdir_id_base32,
desc_id_base32);
/* XXX++?? tor_assert(strlen(hsdir_desc_comb_id) ==
LAST_HID_SERV_REQUEST_KEY_LEN); */
if (set) {
time_t *oldptr;
last_request_ptr = tor_malloc_zero(sizeof(time_t));
*last_request_ptr = now;
oldptr = strmap_set(last_hid_serv_requests, hsdir_desc_comb_id,
last_request_ptr);
tor_free(oldptr);
} else
last_request_ptr = strmap_get_lc(last_hid_serv_requests,
hsdir_desc_comb_id);
return (last_request_ptr) ? *last_request_ptr : 0;
}
/** Clean the history of request times to hidden service directories, so that
* it does not contain requests older than REND_HID_SERV_DIR_REQUERY_PERIOD
* seconds any more. */
static void
directory_clean_last_hid_serv_requests(time_t now)
{
strmap_iter_t *iter;
time_t cutoff = now - hsdir_requery_period(get_options());
strmap_t *last_hid_serv_requests = get_last_hid_serv_requests();
for (iter = strmap_iter_init(last_hid_serv_requests);
!strmap_iter_done(iter); ) {
const char *key;
void *val;
time_t *ent;
strmap_iter_get(iter, &key, &val);
ent = (time_t *) val;
if (*ent < cutoff) {
iter = strmap_iter_next_rmv(last_hid_serv_requests, iter);
tor_free(ent);
} else {
iter = strmap_iter_next(last_hid_serv_requests, iter);
}
}
}
/** Remove all requests related to the descriptor ID <b>desc_id</b> from the
* history of times of requests to hidden service directories.
* <b>desc_id</b> is an unencoded descriptor ID of size DIGEST_LEN.
*
* This is called from rend_client_note_connection_attempt_ended(), which
* must be idempotent, so any future changes to this function must leave it
* idempotent too. */
static void
purge_hid_serv_from_last_hid_serv_requests(const char *desc_id)
{
strmap_iter_t *iter;
strmap_t *last_hid_serv_requests = get_last_hid_serv_requests();
char desc_id_base32[REND_DESC_ID_V2_LEN_BASE32 + 1];
/* Key is stored with the base32 encoded desc_id. */
base32_encode(desc_id_base32, sizeof(desc_id_base32), desc_id,
DIGEST_LEN);
for (iter = strmap_iter_init(last_hid_serv_requests);
!strmap_iter_done(iter); ) {
const char *key;
void *val;
strmap_iter_get(iter, &key, &val);
/* XXX++?? tor_assert(strlen(key) == LAST_HID_SERV_REQUEST_KEY_LEN); */
if (tor_memeq(key + LAST_HID_SERV_REQUEST_KEY_LEN -
REND_DESC_ID_V2_LEN_BASE32,
desc_id_base32,
REND_DESC_ID_V2_LEN_BASE32)) {
iter = strmap_iter_next_rmv(last_hid_serv_requests, iter);
tor_free(val);
} else {
iter = strmap_iter_next(last_hid_serv_requests, iter);
}
}
}
/** Purge the history of request times to hidden service directories,
* so that future lookups of an HS descriptor will not fail because we
* accessed all of the HSDir relays responsible for the descriptor
* recently. */
void
rend_client_purge_last_hid_serv_requests(void)
{
/* Don't create the table if it doesn't exist yet (and it may very
* well not exist if the user hasn't accessed any HSes)... */
strmap_t *old_last_hid_serv_requests = last_hid_serv_requests_;
/* ... and let get_last_hid_serv_requests re-create it for us if
* necessary. */
last_hid_serv_requests_ = NULL;
if (old_last_hid_serv_requests != NULL) {
log_info(LD_REND, "Purging client last-HS-desc-request-time table");
strmap_free(old_last_hid_serv_requests, tor_free_);
}
}
/** This returns a good valid hs dir that should be used for the given
* descriptor id.
*
* Return NULL on error else the hsdir node pointer. */
static routerstatus_t *
pick_hsdir(const char *desc_id, const char *desc_id_base32)
{
smartlist_t *responsible_dirs = smartlist_new();
smartlist_t *usable_responsible_dirs = smartlist_new();
const or_options_t *options = get_options();
routerstatus_t *hs_dir;
time_t now = time(NULL);
int excluded_some;
tor_assert(desc_id);
tor_assert(desc_id_base32);
/* Determine responsible dirs. Even if we can't get all we want, work with
* the ones we have. If it's empty, we'll notice below. */
hid_serv_get_responsible_directories(responsible_dirs, desc_id);
/* Clean request history first. */
directory_clean_last_hid_serv_requests(now);
/* Only select those hidden service directories to which we did not send a
* request recently and for which we have a router descriptor here. */
SMARTLIST_FOREACH_BEGIN(responsible_dirs, routerstatus_t *, dir) {
time_t last = lookup_last_hid_serv_request(dir, desc_id_base32,
0, 0);
const node_t *node = node_get_by_id(dir->identity_digest);
if (last + hsdir_requery_period(options) >= now ||
!node || !node_has_descriptor(node)) {
SMARTLIST_DEL_CURRENT(responsible_dirs, dir);
continue;
}
if (!routerset_contains_node(options->ExcludeNodes, node)) {
smartlist_add(usable_responsible_dirs, dir);
}
} SMARTLIST_FOREACH_END(dir);
excluded_some =
smartlist_len(usable_responsible_dirs) < smartlist_len(responsible_dirs);
hs_dir = smartlist_choose(usable_responsible_dirs);
if (!hs_dir && !options->StrictNodes) {
hs_dir = smartlist_choose(responsible_dirs);
}
smartlist_free(responsible_dirs);
smartlist_free(usable_responsible_dirs);
if (!hs_dir) {
log_info(LD_REND, "Could not pick one of the responsible hidden "
"service directories, because we requested them all "
"recently without success.");
if (options->StrictNodes && excluded_some) {
log_warn(LD_REND, "Could not pick a hidden service directory for the "
"requested hidden service: they are all either down or "
"excluded, and StrictNodes is set.");
}
} else {
/* Remember that we are requesting a descriptor from this hidden service
* directory now. */
lookup_last_hid_serv_request(hs_dir, desc_id_base32, now, 1);
}
return hs_dir;
}
/** Determine the responsible hidden service directories for <b>desc_id</b>
* and fetch the descriptor with that ID from one of them. Only
* send a request to a hidden service directory that we have not yet tried

View File

@ -24,7 +24,6 @@ int rend_client_introduction_acked(origin_circuit_t *circ,
void rend_client_refetch_v2_renddesc(rend_data_t *rend_query);
int rend_client_fetch_v2_desc(rend_data_t *query, smartlist_t *hsdirs);
void rend_client_cancel_descriptor_fetches(void);
void rend_client_purge_last_hid_serv_requests(void);
int rend_client_report_intro_point_failure(extend_info_t *failed_intro,
rend_data_t *rend_data,