Loading changes/bug18809 0 → 100644 +14 −0 Original line number Diff line number Diff line o Major bugfixes (bootstrap): - Check if bootstrap consensus downloads are still needed when the linked connection attaches. This prevents tor making unnecessary begindir-style connections, which are the only directory connections tor clients make since #18483 was merged. - Fix some edge cases where consensus download connections may not have been closed, even though they were not needed. - Make relays retry consensus downloads the correct number of times, rather than the more aggresive client retry count. - Stop downloading consensuses when we have a consensus, even if we don't have all the certificates for it yet. Closes ticket 18943, bugfix on #4483 in 0.2.8.1-alpha, patches by arma and teor. src/or/circuituse.c +19 −0 Original line number Diff line number Diff line Loading @@ -2360,6 +2360,25 @@ connection_ap_handshake_attach_circuit(entry_connection_t *conn) /* we're a general conn */ origin_circuit_t *circ=NULL; /* Are we linked to a dir conn that aims to fetch a consensus? * We check here because this conn might no longer be needed. */ if (base_conn->linked_conn && base_conn->linked_conn->type == CONN_TYPE_DIR && base_conn->linked_conn->purpose == DIR_PURPOSE_FETCH_CONSENSUS) { /* Yes we are. Is there a consensus fetch farther along than us? */ if (networkstatus_consensus_is_already_downloading( TO_DIR_CONN(base_conn->linked_conn)->requested_resource)) { /* We're doing the "multiple consensus fetch attempts" game from * proposal 210, and we're late to the party. Just close this conn. * The circuit and TLS conn that we made will time out after a while * if nothing else wants to use them. */ log_info(LD_DIR, "Closing extra consensus fetch (to %s) since one " "is already downloading.", base_conn->linked_conn->address); return -1; } } if (conn->chosen_exit_name) { const node_t *node = node_get_by_nickname(conn->chosen_exit_name, 1); int opt = conn->chosen_exit_optional; Loading src/or/connection.c +0 −45 Original line number Diff line number Diff line Loading @@ -4438,32 +4438,6 @@ connection_get_by_type_state_rendquery(int type, int state, )); } #define CONN_FIRST_AND_FREE_TEMPLATE(sl) \ STMT_BEGIN \ if (smartlist_len(sl) > 0) { \ void *first_item = smartlist_get(sl, 0); \ smartlist_free(sl); \ return first_item; \ } else { \ smartlist_free(sl); \ return NULL; \ } \ STMT_END /** Return a directory connection (if any one exists) that is fetching * the item described by <b>purpose</b>/<b>resource</b>, otherwise return NULL. */ dir_connection_t * connection_dir_get_by_purpose_and_resource( int purpose, const char *resource) { smartlist_t *conns = connection_dir_list_by_purpose_and_resource( purpose, resource); CONN_FIRST_AND_FREE_TEMPLATE(conns); } /** Return a new smartlist of dir_connection_t * from get_connection_array() * that satisfy conn_test on connection_t *conn_var, and dirconn_test on * dir_connection_t *dirconn_var. conn_var must be of CONN_TYPE_DIR and not Loading Loading @@ -4504,25 +4478,6 @@ connection_dir_list_by_purpose_and_resource( dirconn->requested_resource)); } /** Return a directory connection (if any one exists) that is fetching * the item described by <b>purpose</b>/<b>resource</b>/<b>state</b>, * otherwise return NULL. */ dir_connection_t * connection_dir_get_by_purpose_resource_and_state( int purpose, const char *resource, int state) { smartlist_t *conns = connection_dir_list_by_purpose_resource_and_state( purpose, resource, state); CONN_FIRST_AND_FREE_TEMPLATE(conns); } #undef CONN_FIRST_AND_FREE_TEMPLATE /** Return a list of directory connections that are fetching the item * described by <b>purpose</b>/<b>resource</b>/<b>state</b>. If there are * none, return an empty list. This list must be freed using smartlist_free, Loading src/or/connection.h +0 −7 Original line number Diff line number Diff line Loading @@ -192,13 +192,6 @@ MOCK_DECL(connection_t *,connection_get_by_type_addr_port_purpose,(int type, connection_t *connection_get_by_type_state(int type, int state); connection_t *connection_get_by_type_state_rendquery(int type, int state, const char *rendquery); dir_connection_t *connection_dir_get_by_purpose_and_resource( int purpose, const char *resource); dir_connection_t *connection_dir_get_by_purpose_resource_and_state( int purpose, const char *resource, int state); smartlist_t *connection_dir_list_by_purpose_and_resource( int purpose, const char *resource); Loading src/or/directory.c +30 −234 Original line number Diff line number Diff line Loading @@ -96,6 +96,9 @@ static void directory_initiate_command_rend( time_t if_modified_since, const rend_data_t *rend_query); static void connection_dir_close_consensus_fetches( dir_connection_t *except_this_one, const char *resource); /********* START VARIABLES **********/ /** How far in the future do we allow a directory server to tell us it is Loading Loading @@ -1170,12 +1173,6 @@ directory_initiate_command_rend(const tor_addr_port_t *or_addr_port, return; } /* ensure we don't make excess connections when we're already downloading * a consensus during bootstrap */ if (connection_dir_avoid_extra_connection_for_purpose(dir_purpose)) { return; } conn = dir_connection_new(tor_addr_family(&addr)); /* set up conn so it's got all the data we need to remember */ Loading Loading @@ -1216,11 +1213,6 @@ directory_initiate_command_rend(const tor_addr_port_t *or_addr_port, conn->base_.state = DIR_CONN_STATE_CLIENT_SENDING; /* fall through */ case 0: /* Close this connection if there's another consensus connection * downloading (during bootstrap), or connecting (after bootstrap). */ if (connection_dir_close_consensus_conn_if_extra(conn)) { return; } /* queue the command on the outbuf */ directory_send_command(conn, dir_purpose, 1, resource, payload, payload_len, Loading Loading @@ -1268,11 +1260,6 @@ directory_initiate_command_rend(const tor_addr_port_t *or_addr_port, connection_mark_for_close(TO_CONN(conn)); return; } /* Close this connection if there's another consensus connection * downloading (during bootstrap), or connecting (after bootstrap). */ if (connection_dir_close_consensus_conn_if_extra(conn)) { return; } conn->base_.state = DIR_CONN_STATE_CLIENT_SENDING; /* queue the command on the outbuf */ directory_send_command(conn, dir_purpose, 0, resource, Loading Loading @@ -2028,6 +2015,10 @@ connection_dir_client_reached_eof(dir_connection_t *conn) networkstatus_consensus_download_failed(0, flavname); return -1; } /* If we launched other fetches for this consensus, cancel them. */ connection_dir_close_consensus_fetches(conn, flavname); /* launches router downloads as needed */ routers_update_all_from_networkstatus(now, 3); update_microdescs_from_networkstatus(now); Loading Loading @@ -3679,226 +3670,37 @@ connection_dir_finished_flushing(dir_connection_t *conn) return 0; } /* A helper function for connection_dir_close_consensus_conn_if_extra() * and connection_dir_close_extra_consensus_conns() that returns 0 if * we can't have, or don't want to close, excess consensus connections. */ STATIC int connection_dir_would_close_consensus_conn_helper(void) { const or_options_t *options = get_options(); /* we're only interested in closing excess connections if we could * have created any in the first place */ if (!networkstatus_consensus_can_use_multiple_directories(options)) { return 0; } /* We want to close excess connections downloading a consensus. * If there aren't any excess, we don't have anything to close. */ if (!networkstatus_consensus_has_excess_connections()) { return 0; } /* If we have excess connections, but none of them are downloading a * consensus, and we are still bootstrapping (that is, we have no usable * consensus), we don't want to close any until one starts downloading. */ if (!networkstatus_consensus_is_downloading_usable_flavor() && networkstatus_consensus_is_boostrapping(time(NULL))) { return 0; } /* If we have just stopped bootstrapping (that is, just parsed a consensus), * we might still have some excess connections hanging around. So we still * have to check if we want to close any, even if we've stopped * bootstrapping. */ return 1; } /* Check if we would close excess consensus connections. If we would, any * new consensus connection would become excess immediately, so return 1. * Otherwise, return 0. */ int connection_dir_avoid_extra_connection_for_purpose(unsigned int purpose) { const or_options_t *options = get_options(); /* We're not interested in connections that aren't fetching a consensus. */ if (purpose != DIR_PURPOSE_FETCH_CONSENSUS) { return 0; } /* we're only interested in avoiding excess connections if we could * have created any in the first place */ if (!networkstatus_consensus_can_use_multiple_directories(options)) { return 0; } /* If there are connections downloading a consensus, and we are still * bootstrapping (that is, we have no usable consensus), we can be sure that * any further connections would be excess. */ if (networkstatus_consensus_is_downloading_usable_flavor() && networkstatus_consensus_is_boostrapping(time(NULL))) { return 1; } return 0; } /* Check if we have more than one consensus download connection attempt, and * close conn: * - if we don't have a consensus, and we're downloading a consensus, and conn * is not downloading a consensus yet; * - if we do have a consensus, and there's more than one consensus connection. /* We just got a new consensus! If there are other in-progress requests * for this consensus flavor (for example because we launched several in * parallel), cancel them. * * Post-bootstrap consensus connection attempts are initiated one at a time. * So this function won't close any consensus connection attempts that * are initiated after bootstrap. */ int connection_dir_close_consensus_conn_if_extra(dir_connection_t *conn) { tor_assert(conn); tor_assert(conn->base_.type == CONN_TYPE_DIR); /* We're not interested in connections that aren't fetching a consensus. */ if (conn->base_.purpose != DIR_PURPOSE_FETCH_CONSENSUS) { return 0; } /* The connection has already been closed */ if (conn->base_.marked_for_close) { return 0; } /* Only close this connection if there's another consensus connection * downloading (during bootstrap), or connecting (after bootstrap). * Post-bootstrap consensus connection attempts won't be closed, because * they only occur one at a time. */ if (!connection_dir_would_close_consensus_conn_helper()) { return 0; } const int we_are_bootstrapping = networkstatus_consensus_is_boostrapping( time(NULL)); /* We don't want to check other connections to see if they are downloading, * as this is prone to race-conditions. So leave it for * connection_dir_consider_close_extra_consensus_conns() to clean up. * We do this check here (not just in * connection_ap_handshake_attach_circuit()) to handle the edge case where * a consensus fetch begins and ends before some other one tries to attach to * a circuit, in which case the other one won't know that we're all happy now. * * But if conn has just started connecting, or we have a consensus already, * we can be sure it's not needed any more. */ if (!we_are_bootstrapping || conn->base_.state == DIR_CONN_STATE_CONNECTING) { connection_close_immediate(&conn->base_); connection_mark_for_close(&conn->base_); return -1; } return 0; } /* Clean up excess consensus download connection attempts. * During bootstrap, or when the bootstrap consensus has just been downloaded, * if we have more than one active consensus connection: * - if we don't have a consensus, and we're downloading a consensus, keep an * earlier connection, or a connection to a fallback directory, and close * all other connections; * - if we have just downloaded the bootstrap consensus, and have other * consensus connections left over, close all of them. * * Post-bootstrap consensus connection attempts are initiated one at a time. * So this function won't close any consensus connection attempts that * are initiated after bootstrap. * Don't mark the conn that just gave us the consensus -- otherwise we * would end up double-marking it when it cleans itself up. */ void connection_dir_close_extra_consensus_conns(void) static void connection_dir_close_consensus_fetches(dir_connection_t *except_this_one, const char *resource) { /* Only cleanup connections if there is more than one consensus connection, * and at least one of those connections is already downloading * (during bootstrap), or connecting (just after the bootstrap consensus is * downloaded). * Post-bootstrap consensus connection attempts won't be cleaned up, because * they only occur one at a time. */ if (!connection_dir_would_close_consensus_conn_helper()) { return; } int we_are_bootstrapping = networkstatus_consensus_is_boostrapping( time(NULL)); const char *usable_resource = networkstatus_get_flavor_name( usable_consensus_flavor()); smartlist_t *consens_usable_conns = connection_dir_list_by_purpose_and_resource( DIR_PURPOSE_FETCH_CONSENSUS, usable_resource); /* If we want to keep a connection that's downloading, find a connection to * keep, favouring: * - connections opened earlier (they are likely to have progressed further) * - connections to fallbacks (to reduce the load on authorities) */ dir_connection_t *kept_download_conn = NULL; int kept_is_authority = 0; if (we_are_bootstrapping) { SMARTLIST_FOREACH_BEGIN(consens_usable_conns, dir_connection_t *, d) { tor_assert(d); int d_is_authority = router_digest_is_trusted_dir(d->identity_digest); /* keep the first connection that is past the connecting state, but * prefer fallbacks. */ if (d->base_.state != DIR_CONN_STATE_CONNECTING) { if (!kept_download_conn || (kept_is_authority && !d_is_authority)) { kept_download_conn = d; kept_is_authority = d_is_authority; /* we've found the earliest fallback, and want to keep it regardless * of any other connections */ if (!kept_is_authority) break; } } } SMARTLIST_FOREACH_END(d); } SMARTLIST_FOREACH_BEGIN(consens_usable_conns, dir_connection_t *, d) { tor_assert(d); /* don't close this connection if it's the one we want to keep */ if (kept_download_conn && d == kept_download_conn) smartlist_t *conns_to_close = connection_dir_list_by_purpose_and_resource(DIR_PURPOSE_FETCH_CONSENSUS, resource); SMARTLIST_FOREACH_BEGIN(conns_to_close, dir_connection_t *, d) { if (d == except_this_one) continue; /* mark all other connections for close */ if (!d->base_.marked_for_close) { connection_close_immediate(&d->base_); connection_mark_for_close(&d->base_); } log_info(LD_DIR, "Closing consensus fetch (to %s) since one " "has just arrived.", TO_CONN(d)->address); connection_mark_for_close(TO_CONN(d)); } SMARTLIST_FOREACH_END(d); smartlist_free(consens_usable_conns); consens_usable_conns = NULL; /* make sure we've closed all excess connections */ const int final_connecting_conn_count = connection_dir_count_by_purpose_resource_and_state( DIR_PURPOSE_FETCH_CONSENSUS, usable_resource, DIR_CONN_STATE_CONNECTING); if (final_connecting_conn_count > 0) { log_warn(LD_BUG, "Expected 0 consensus connections connecting after " "cleanup, got %d.", final_connecting_conn_count); } const int expected_final_conn_count = (we_are_bootstrapping ? 1 : 0); const int final_conn_count = connection_dir_count_by_purpose_and_resource( DIR_PURPOSE_FETCH_CONSENSUS, usable_resource); if (final_conn_count > expected_final_conn_count) { log_warn(LD_BUG, "Expected %d consensus connections after cleanup, got " "%d.", expected_final_conn_count, final_connecting_conn_count); } smartlist_free(conns_to_close); } /** Connected handler for directory connections: begin sending data to the * server, and return 0, or, if the connection is an excess bootstrap * connection, close all excess bootstrap connections. * server, and return 0. * Only used when connections don't immediately connect. */ int connection_dir_finished_connecting(dir_connection_t *conn) Loading @@ -3910,12 +3712,6 @@ connection_dir_finished_connecting(dir_connection_t *conn) log_debug(LD_HTTP,"Dir connection to router %s:%u established.", conn->base_.address,conn->base_.port); /* Close this connection if there's another consensus connection * downloading (during bootstrap), or connecting (after bootstrap). */ if (connection_dir_close_consensus_conn_if_extra(conn)) { return -1; } /* start flushing conn */ conn->base_.state = DIR_CONN_STATE_CLIENT_SENDING; return 0; Loading @@ -3932,7 +3728,7 @@ find_dl_schedule(download_status_t *dls, const or_options_t *options) const int dir_server = dir_server_mode(options); const int multi_d = networkstatus_consensus_can_use_multiple_directories( options); const int we_are_bootstrapping = networkstatus_consensus_is_boostrapping( const int we_are_bootstrapping = networkstatus_consensus_is_bootstrapping( time(NULL)); const int use_fallbacks = networkstatus_consensus_can_use_extra_fallbacks( options); Loading Loading
changes/bug18809 0 → 100644 +14 −0 Original line number Diff line number Diff line o Major bugfixes (bootstrap): - Check if bootstrap consensus downloads are still needed when the linked connection attaches. This prevents tor making unnecessary begindir-style connections, which are the only directory connections tor clients make since #18483 was merged. - Fix some edge cases where consensus download connections may not have been closed, even though they were not needed. - Make relays retry consensus downloads the correct number of times, rather than the more aggresive client retry count. - Stop downloading consensuses when we have a consensus, even if we don't have all the certificates for it yet. Closes ticket 18943, bugfix on #4483 in 0.2.8.1-alpha, patches by arma and teor.
src/or/circuituse.c +19 −0 Original line number Diff line number Diff line Loading @@ -2360,6 +2360,25 @@ connection_ap_handshake_attach_circuit(entry_connection_t *conn) /* we're a general conn */ origin_circuit_t *circ=NULL; /* Are we linked to a dir conn that aims to fetch a consensus? * We check here because this conn might no longer be needed. */ if (base_conn->linked_conn && base_conn->linked_conn->type == CONN_TYPE_DIR && base_conn->linked_conn->purpose == DIR_PURPOSE_FETCH_CONSENSUS) { /* Yes we are. Is there a consensus fetch farther along than us? */ if (networkstatus_consensus_is_already_downloading( TO_DIR_CONN(base_conn->linked_conn)->requested_resource)) { /* We're doing the "multiple consensus fetch attempts" game from * proposal 210, and we're late to the party. Just close this conn. * The circuit and TLS conn that we made will time out after a while * if nothing else wants to use them. */ log_info(LD_DIR, "Closing extra consensus fetch (to %s) since one " "is already downloading.", base_conn->linked_conn->address); return -1; } } if (conn->chosen_exit_name) { const node_t *node = node_get_by_nickname(conn->chosen_exit_name, 1); int opt = conn->chosen_exit_optional; Loading
src/or/connection.c +0 −45 Original line number Diff line number Diff line Loading @@ -4438,32 +4438,6 @@ connection_get_by_type_state_rendquery(int type, int state, )); } #define CONN_FIRST_AND_FREE_TEMPLATE(sl) \ STMT_BEGIN \ if (smartlist_len(sl) > 0) { \ void *first_item = smartlist_get(sl, 0); \ smartlist_free(sl); \ return first_item; \ } else { \ smartlist_free(sl); \ return NULL; \ } \ STMT_END /** Return a directory connection (if any one exists) that is fetching * the item described by <b>purpose</b>/<b>resource</b>, otherwise return NULL. */ dir_connection_t * connection_dir_get_by_purpose_and_resource( int purpose, const char *resource) { smartlist_t *conns = connection_dir_list_by_purpose_and_resource( purpose, resource); CONN_FIRST_AND_FREE_TEMPLATE(conns); } /** Return a new smartlist of dir_connection_t * from get_connection_array() * that satisfy conn_test on connection_t *conn_var, and dirconn_test on * dir_connection_t *dirconn_var. conn_var must be of CONN_TYPE_DIR and not Loading Loading @@ -4504,25 +4478,6 @@ connection_dir_list_by_purpose_and_resource( dirconn->requested_resource)); } /** Return a directory connection (if any one exists) that is fetching * the item described by <b>purpose</b>/<b>resource</b>/<b>state</b>, * otherwise return NULL. */ dir_connection_t * connection_dir_get_by_purpose_resource_and_state( int purpose, const char *resource, int state) { smartlist_t *conns = connection_dir_list_by_purpose_resource_and_state( purpose, resource, state); CONN_FIRST_AND_FREE_TEMPLATE(conns); } #undef CONN_FIRST_AND_FREE_TEMPLATE /** Return a list of directory connections that are fetching the item * described by <b>purpose</b>/<b>resource</b>/<b>state</b>. If there are * none, return an empty list. This list must be freed using smartlist_free, Loading
src/or/connection.h +0 −7 Original line number Diff line number Diff line Loading @@ -192,13 +192,6 @@ MOCK_DECL(connection_t *,connection_get_by_type_addr_port_purpose,(int type, connection_t *connection_get_by_type_state(int type, int state); connection_t *connection_get_by_type_state_rendquery(int type, int state, const char *rendquery); dir_connection_t *connection_dir_get_by_purpose_and_resource( int purpose, const char *resource); dir_connection_t *connection_dir_get_by_purpose_resource_and_state( int purpose, const char *resource, int state); smartlist_t *connection_dir_list_by_purpose_and_resource( int purpose, const char *resource); Loading
src/or/directory.c +30 −234 Original line number Diff line number Diff line Loading @@ -96,6 +96,9 @@ static void directory_initiate_command_rend( time_t if_modified_since, const rend_data_t *rend_query); static void connection_dir_close_consensus_fetches( dir_connection_t *except_this_one, const char *resource); /********* START VARIABLES **********/ /** How far in the future do we allow a directory server to tell us it is Loading Loading @@ -1170,12 +1173,6 @@ directory_initiate_command_rend(const tor_addr_port_t *or_addr_port, return; } /* ensure we don't make excess connections when we're already downloading * a consensus during bootstrap */ if (connection_dir_avoid_extra_connection_for_purpose(dir_purpose)) { return; } conn = dir_connection_new(tor_addr_family(&addr)); /* set up conn so it's got all the data we need to remember */ Loading Loading @@ -1216,11 +1213,6 @@ directory_initiate_command_rend(const tor_addr_port_t *or_addr_port, conn->base_.state = DIR_CONN_STATE_CLIENT_SENDING; /* fall through */ case 0: /* Close this connection if there's another consensus connection * downloading (during bootstrap), or connecting (after bootstrap). */ if (connection_dir_close_consensus_conn_if_extra(conn)) { return; } /* queue the command on the outbuf */ directory_send_command(conn, dir_purpose, 1, resource, payload, payload_len, Loading Loading @@ -1268,11 +1260,6 @@ directory_initiate_command_rend(const tor_addr_port_t *or_addr_port, connection_mark_for_close(TO_CONN(conn)); return; } /* Close this connection if there's another consensus connection * downloading (during bootstrap), or connecting (after bootstrap). */ if (connection_dir_close_consensus_conn_if_extra(conn)) { return; } conn->base_.state = DIR_CONN_STATE_CLIENT_SENDING; /* queue the command on the outbuf */ directory_send_command(conn, dir_purpose, 0, resource, Loading Loading @@ -2028,6 +2015,10 @@ connection_dir_client_reached_eof(dir_connection_t *conn) networkstatus_consensus_download_failed(0, flavname); return -1; } /* If we launched other fetches for this consensus, cancel them. */ connection_dir_close_consensus_fetches(conn, flavname); /* launches router downloads as needed */ routers_update_all_from_networkstatus(now, 3); update_microdescs_from_networkstatus(now); Loading Loading @@ -3679,226 +3670,37 @@ connection_dir_finished_flushing(dir_connection_t *conn) return 0; } /* A helper function for connection_dir_close_consensus_conn_if_extra() * and connection_dir_close_extra_consensus_conns() that returns 0 if * we can't have, or don't want to close, excess consensus connections. */ STATIC int connection_dir_would_close_consensus_conn_helper(void) { const or_options_t *options = get_options(); /* we're only interested in closing excess connections if we could * have created any in the first place */ if (!networkstatus_consensus_can_use_multiple_directories(options)) { return 0; } /* We want to close excess connections downloading a consensus. * If there aren't any excess, we don't have anything to close. */ if (!networkstatus_consensus_has_excess_connections()) { return 0; } /* If we have excess connections, but none of them are downloading a * consensus, and we are still bootstrapping (that is, we have no usable * consensus), we don't want to close any until one starts downloading. */ if (!networkstatus_consensus_is_downloading_usable_flavor() && networkstatus_consensus_is_boostrapping(time(NULL))) { return 0; } /* If we have just stopped bootstrapping (that is, just parsed a consensus), * we might still have some excess connections hanging around. So we still * have to check if we want to close any, even if we've stopped * bootstrapping. */ return 1; } /* Check if we would close excess consensus connections. If we would, any * new consensus connection would become excess immediately, so return 1. * Otherwise, return 0. */ int connection_dir_avoid_extra_connection_for_purpose(unsigned int purpose) { const or_options_t *options = get_options(); /* We're not interested in connections that aren't fetching a consensus. */ if (purpose != DIR_PURPOSE_FETCH_CONSENSUS) { return 0; } /* we're only interested in avoiding excess connections if we could * have created any in the first place */ if (!networkstatus_consensus_can_use_multiple_directories(options)) { return 0; } /* If there are connections downloading a consensus, and we are still * bootstrapping (that is, we have no usable consensus), we can be sure that * any further connections would be excess. */ if (networkstatus_consensus_is_downloading_usable_flavor() && networkstatus_consensus_is_boostrapping(time(NULL))) { return 1; } return 0; } /* Check if we have more than one consensus download connection attempt, and * close conn: * - if we don't have a consensus, and we're downloading a consensus, and conn * is not downloading a consensus yet; * - if we do have a consensus, and there's more than one consensus connection. /* We just got a new consensus! If there are other in-progress requests * for this consensus flavor (for example because we launched several in * parallel), cancel them. * * Post-bootstrap consensus connection attempts are initiated one at a time. * So this function won't close any consensus connection attempts that * are initiated after bootstrap. */ int connection_dir_close_consensus_conn_if_extra(dir_connection_t *conn) { tor_assert(conn); tor_assert(conn->base_.type == CONN_TYPE_DIR); /* We're not interested in connections that aren't fetching a consensus. */ if (conn->base_.purpose != DIR_PURPOSE_FETCH_CONSENSUS) { return 0; } /* The connection has already been closed */ if (conn->base_.marked_for_close) { return 0; } /* Only close this connection if there's another consensus connection * downloading (during bootstrap), or connecting (after bootstrap). * Post-bootstrap consensus connection attempts won't be closed, because * they only occur one at a time. */ if (!connection_dir_would_close_consensus_conn_helper()) { return 0; } const int we_are_bootstrapping = networkstatus_consensus_is_boostrapping( time(NULL)); /* We don't want to check other connections to see if they are downloading, * as this is prone to race-conditions. So leave it for * connection_dir_consider_close_extra_consensus_conns() to clean up. * We do this check here (not just in * connection_ap_handshake_attach_circuit()) to handle the edge case where * a consensus fetch begins and ends before some other one tries to attach to * a circuit, in which case the other one won't know that we're all happy now. * * But if conn has just started connecting, or we have a consensus already, * we can be sure it's not needed any more. */ if (!we_are_bootstrapping || conn->base_.state == DIR_CONN_STATE_CONNECTING) { connection_close_immediate(&conn->base_); connection_mark_for_close(&conn->base_); return -1; } return 0; } /* Clean up excess consensus download connection attempts. * During bootstrap, or when the bootstrap consensus has just been downloaded, * if we have more than one active consensus connection: * - if we don't have a consensus, and we're downloading a consensus, keep an * earlier connection, or a connection to a fallback directory, and close * all other connections; * - if we have just downloaded the bootstrap consensus, and have other * consensus connections left over, close all of them. * * Post-bootstrap consensus connection attempts are initiated one at a time. * So this function won't close any consensus connection attempts that * are initiated after bootstrap. * Don't mark the conn that just gave us the consensus -- otherwise we * would end up double-marking it when it cleans itself up. */ void connection_dir_close_extra_consensus_conns(void) static void connection_dir_close_consensus_fetches(dir_connection_t *except_this_one, const char *resource) { /* Only cleanup connections if there is more than one consensus connection, * and at least one of those connections is already downloading * (during bootstrap), or connecting (just after the bootstrap consensus is * downloaded). * Post-bootstrap consensus connection attempts won't be cleaned up, because * they only occur one at a time. */ if (!connection_dir_would_close_consensus_conn_helper()) { return; } int we_are_bootstrapping = networkstatus_consensus_is_boostrapping( time(NULL)); const char *usable_resource = networkstatus_get_flavor_name( usable_consensus_flavor()); smartlist_t *consens_usable_conns = connection_dir_list_by_purpose_and_resource( DIR_PURPOSE_FETCH_CONSENSUS, usable_resource); /* If we want to keep a connection that's downloading, find a connection to * keep, favouring: * - connections opened earlier (they are likely to have progressed further) * - connections to fallbacks (to reduce the load on authorities) */ dir_connection_t *kept_download_conn = NULL; int kept_is_authority = 0; if (we_are_bootstrapping) { SMARTLIST_FOREACH_BEGIN(consens_usable_conns, dir_connection_t *, d) { tor_assert(d); int d_is_authority = router_digest_is_trusted_dir(d->identity_digest); /* keep the first connection that is past the connecting state, but * prefer fallbacks. */ if (d->base_.state != DIR_CONN_STATE_CONNECTING) { if (!kept_download_conn || (kept_is_authority && !d_is_authority)) { kept_download_conn = d; kept_is_authority = d_is_authority; /* we've found the earliest fallback, and want to keep it regardless * of any other connections */ if (!kept_is_authority) break; } } } SMARTLIST_FOREACH_END(d); } SMARTLIST_FOREACH_BEGIN(consens_usable_conns, dir_connection_t *, d) { tor_assert(d); /* don't close this connection if it's the one we want to keep */ if (kept_download_conn && d == kept_download_conn) smartlist_t *conns_to_close = connection_dir_list_by_purpose_and_resource(DIR_PURPOSE_FETCH_CONSENSUS, resource); SMARTLIST_FOREACH_BEGIN(conns_to_close, dir_connection_t *, d) { if (d == except_this_one) continue; /* mark all other connections for close */ if (!d->base_.marked_for_close) { connection_close_immediate(&d->base_); connection_mark_for_close(&d->base_); } log_info(LD_DIR, "Closing consensus fetch (to %s) since one " "has just arrived.", TO_CONN(d)->address); connection_mark_for_close(TO_CONN(d)); } SMARTLIST_FOREACH_END(d); smartlist_free(consens_usable_conns); consens_usable_conns = NULL; /* make sure we've closed all excess connections */ const int final_connecting_conn_count = connection_dir_count_by_purpose_resource_and_state( DIR_PURPOSE_FETCH_CONSENSUS, usable_resource, DIR_CONN_STATE_CONNECTING); if (final_connecting_conn_count > 0) { log_warn(LD_BUG, "Expected 0 consensus connections connecting after " "cleanup, got %d.", final_connecting_conn_count); } const int expected_final_conn_count = (we_are_bootstrapping ? 1 : 0); const int final_conn_count = connection_dir_count_by_purpose_and_resource( DIR_PURPOSE_FETCH_CONSENSUS, usable_resource); if (final_conn_count > expected_final_conn_count) { log_warn(LD_BUG, "Expected %d consensus connections after cleanup, got " "%d.", expected_final_conn_count, final_connecting_conn_count); } smartlist_free(conns_to_close); } /** Connected handler for directory connections: begin sending data to the * server, and return 0, or, if the connection is an excess bootstrap * connection, close all excess bootstrap connections. * server, and return 0. * Only used when connections don't immediately connect. */ int connection_dir_finished_connecting(dir_connection_t *conn) Loading @@ -3910,12 +3712,6 @@ connection_dir_finished_connecting(dir_connection_t *conn) log_debug(LD_HTTP,"Dir connection to router %s:%u established.", conn->base_.address,conn->base_.port); /* Close this connection if there's another consensus connection * downloading (during bootstrap), or connecting (after bootstrap). */ if (connection_dir_close_consensus_conn_if_extra(conn)) { return -1; } /* start flushing conn */ conn->base_.state = DIR_CONN_STATE_CLIENT_SENDING; return 0; Loading @@ -3932,7 +3728,7 @@ find_dl_schedule(download_status_t *dls, const or_options_t *options) const int dir_server = dir_server_mode(options); const int multi_d = networkstatus_consensus_can_use_multiple_directories( options); const int we_are_bootstrapping = networkstatus_consensus_is_boostrapping( const int we_are_bootstrapping = networkstatus_consensus_is_bootstrapping( time(NULL)); const int use_fallbacks = networkstatus_consensus_can_use_extra_fallbacks( options); Loading
