/* Copyright (c) 2001 Matej Pfajfar. * Copyright (c) 2001-2004, Roger Dingledine. * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. * Copyright (c) 2007-2013, The Tor Project, Inc. */ /* See LICENSE for licensing information */ /** * \file main.c * \brief Toplevel module. Handles signals, multiplexes between * connections, implements main loop, and drives scheduled events. **/ #define MAIN_PRIVATE #include "or.h" #include "addressmap.h" #include "backtrace.h" #include "buffers.h" #include "channel.h" #include "channeltls.h" #include "circuitbuild.h" #include "circuitlist.h" #include "circuituse.h" #include "command.h" #include "config.h" #include "confparse.h" #include "connection.h" #include "connection_edge.h" #include "connection_or.h" #include "control.h" #include "cpuworker.h" #include "directory.h" #include "dirserv.h" #include "dirvote.h" #include "dns.h" #include "dnsserv.h" #include "entrynodes.h" #include "geoip.h" #include "hibernate.h" #include "main.h" #include "microdesc.h" #include "networkstatus.h" #include "nodelist.h" #include "ntmain.h" #include "onion.h" #include "policies.h" #include "transports.h" #include "relay.h" #include "rendclient.h" #include "rendcommon.h" #include "rendservice.h" #include "rephist.h" #include "router.h" #include "routerlist.h" #include "routerparse.h" #include "statefile.h" #include "status.h" #include "ext_orport.h" #ifdef USE_DMALLOC #include #include #endif #include "memarea.h" #include "../common/sandbox.h" #ifdef HAVE_EVENT2_EVENT_H #include #else #include #endif #ifdef USE_BUFFEREVENTS #include #endif void evdns_shutdown(int); /********* PROTOTYPES **********/ static void dumpmemusage(int severity); static void dumpstats(int severity); /* log stats */ static void conn_read_callback(evutil_socket_t fd, short event, void *_conn); static void conn_write_callback(evutil_socket_t fd, short event, void *_conn); static void second_elapsed_callback(periodic_timer_t *timer, void *args); static int conn_close_if_marked(int i); static void connection_start_reading_from_linked_conn(connection_t *conn); static int connection_should_read_from_linked_conn(connection_t *conn); /********* START VARIABLES **********/ #ifndef USE_BUFFEREVENTS int global_read_bucket; /**< Max number of bytes I can read this second. */ int global_write_bucket; /**< Max number of bytes I can write this second. */ /** Max number of relayed (bandwidth class 1) bytes I can read this second. */ int global_relayed_read_bucket; /** Max number of relayed (bandwidth class 1) bytes I can write this second. */ int global_relayed_write_bucket; /** What was the read bucket before the last second_elapsed_callback() call? * (used to determine how many bytes we've read). */ static int stats_prev_global_read_bucket; /** What was the write bucket before the last second_elapsed_callback() call? * (used to determine how many bytes we've written). */ static int stats_prev_global_write_bucket; #endif /* DOCDOC stats_prev_n_read */ static uint64_t stats_prev_n_read = 0; /* DOCDOC stats_prev_n_written */ static uint64_t stats_prev_n_written = 0; /* XXX we might want to keep stats about global_relayed_*_bucket too. Or not.*/ /** How many bytes have we read since we started the process? */ static uint64_t stats_n_bytes_read = 0; /** How many bytes have we written since we started the process? */ static uint64_t stats_n_bytes_written = 0; /** What time did this process start up? */ time_t time_of_process_start = 0; /** How many seconds have we been running? */ long stats_n_seconds_working = 0; /** When do we next launch DNS wildcarding checks? */ static time_t time_to_check_for_correct_dns = 0; /** How often will we honor SIGNEWNYM requests? */ #define MAX_SIGNEWNYM_RATE 10 /** When did we last process a SIGNEWNYM request? */ static time_t time_of_last_signewnym = 0; /** Is there a signewnym request we're currently waiting to handle? */ static int signewnym_is_pending = 0; /** How many times have we called newnym? */ static unsigned newnym_epoch = 0; /** Smartlist of all open connections. */ static smartlist_t *connection_array = NULL; /** List of connections that have been marked for close and need to be freed * and removed from connection_array. */ static smartlist_t *closeable_connection_lst = NULL; /** List of linked connections that are currently reading data into their * inbuf from their partner's outbuf. */ static smartlist_t *active_linked_connection_lst = NULL; /** Flag: Set to true iff we entered the current libevent main loop via * loop_once. If so, there's no need to trigger a loopexit in order * to handle linked connections. */ static int called_loop_once = 0; /** We set this to 1 when we've opened a circuit, so we can print a log * entry to inform the user that Tor is working. We set it to 0 when * we think the fact that we once opened a circuit doesn't mean we can do so * any longer (a big time jump happened, when we notice our directory is * heinously out-of-date, etc. */ int can_complete_circuit=0; /** How often do we check for router descriptors that we should download * when we have too little directory info? */ #define GREEDY_DESCRIPTOR_RETRY_INTERVAL (10) /** How often do we check for router descriptors that we should download * when we have enough directory info? */ #define LAZY_DESCRIPTOR_RETRY_INTERVAL (60) /** How often do we 'forgive' undownloadable router descriptors and attempt * to download them again? */ #define DESCRIPTOR_FAILURE_RESET_INTERVAL (60*60) /** Decides our behavior when no logs are configured/before any * logs have been configured. For 0, we log notice to stdout as normal. * For 1, we log warnings only. For 2, we log nothing. */ int quiet_level = 0; /********* END VARIABLES ************/ /**************************************************************************** * * This section contains accessors and other methods on the connection_array * variables (which are global within this file and unavailable outside it). * ****************************************************************************/ #if 0 && defined(USE_BUFFEREVENTS) static void free_old_inbuf(connection_t *conn) { if (! conn->inbuf) return; tor_assert(conn->outbuf); tor_assert(buf_datalen(conn->inbuf) == 0); tor_assert(buf_datalen(conn->outbuf) == 0); buf_free(conn->inbuf); buf_free(conn->outbuf); conn->inbuf = conn->outbuf = NULL; if (conn->read_event) { event_del(conn->read_event); tor_event_free(conn->read_event); } if (conn->write_event) { event_del(conn->read_event); tor_event_free(conn->write_event); } conn->read_event = conn->write_event = NULL; } #endif #if defined(_WIN32) && defined(USE_BUFFEREVENTS) /** Remove the kernel-space send and receive buffers for s. For use * with IOCP only. */ static int set_buffer_lengths_to_zero(tor_socket_t s) { int zero = 0; int r = 0; if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, (void*)&zero, sizeof(zero))) { log_warn(LD_NET, "Unable to clear SO_SNDBUF"); r = -1; } if (setsockopt(s, SOL_SOCKET, SO_RCVBUF, (void*)&zero, sizeof(zero))) { log_warn(LD_NET, "Unable to clear SO_RCVBUF"); r = -1; } return r; } #endif /** Add conn to the array of connections that we can poll on. The * connection's socket must be set; the connection starts out * non-reading and non-writing. */ int connection_add_impl(connection_t *conn, int is_connecting) { tor_assert(conn); tor_assert(SOCKET_OK(conn->s) || conn->linked || (conn->type == CONN_TYPE_AP && TO_EDGE_CONN(conn)->is_dns_request)); tor_assert(conn->conn_array_index == -1); /* can only connection_add once */ conn->conn_array_index = smartlist_len(connection_array); smartlist_add(connection_array, conn); #ifdef USE_BUFFEREVENTS if (connection_type_uses_bufferevent(conn)) { if (SOCKET_OK(conn->s) && !conn->linked) { #ifdef _WIN32 if (tor_libevent_using_iocp_bufferevents() && get_options()->UserspaceIOCPBuffers) { set_buffer_lengths_to_zero(conn->s); } #endif conn->bufev = bufferevent_socket_new( tor_libevent_get_base(), conn->s, BEV_OPT_DEFER_CALLBACKS); if (!conn->bufev) { log_warn(LD_BUG, "Unable to create socket bufferevent"); smartlist_del(connection_array, conn->conn_array_index); conn->conn_array_index = -1; return -1; } if (is_connecting) { /* Put the bufferevent into a "connecting" state so that we'll get * a "connected" event callback on successful write. */ bufferevent_socket_connect(conn->bufev, NULL, 0); } connection_configure_bufferevent_callbacks(conn); } else if (conn->linked && conn->linked_conn && connection_type_uses_bufferevent(conn->linked_conn)) { tor_assert(!(SOCKET_OK(conn->s))); if (!conn->bufev) { struct bufferevent *pair[2] = { NULL, NULL }; if (bufferevent_pair_new(tor_libevent_get_base(), BEV_OPT_DEFER_CALLBACKS, pair) < 0) { log_warn(LD_BUG, "Unable to create bufferevent pair"); smartlist_del(connection_array, conn->conn_array_index); conn->conn_array_index = -1; return -1; } tor_assert(pair[0]); conn->bufev = pair[0]; conn->linked_conn->bufev = pair[1]; } /* else the other side already was added, and got a bufferevent_pair */ connection_configure_bufferevent_callbacks(conn); } else { tor_assert(!conn->linked); } if (conn->bufev) tor_assert(conn->inbuf == NULL); if (conn->linked_conn && conn->linked_conn->bufev) tor_assert(conn->linked_conn->inbuf == NULL); } #else (void) is_connecting; #endif if (!HAS_BUFFEREVENT(conn) && (SOCKET_OK(conn->s) || conn->linked)) { conn->read_event = tor_event_new(tor_libevent_get_base(), conn->s, EV_READ|EV_PERSIST, conn_read_callback, conn); conn->write_event = tor_event_new(tor_libevent_get_base(), conn->s, EV_WRITE|EV_PERSIST, conn_write_callback, conn); /* XXXX CHECK FOR NULL RETURN! */ } log_debug(LD_NET,"new conn type %s, socket %d, address %s, n_conns %d.", conn_type_to_string(conn->type), (int)conn->s, conn->address, smartlist_len(connection_array)); return 0; } /** Tell libevent that we don't care about conn any more. */ void connection_unregister_events(connection_t *conn) { if (conn->read_event) { if (event_del(conn->read_event)) log_warn(LD_BUG, "Error removing read event for %d", (int)conn->s); tor_free(conn->read_event); } if (conn->write_event) { if (event_del(conn->write_event)) log_warn(LD_BUG, "Error removing write event for %d", (int)conn->s); tor_free(conn->write_event); } #ifdef USE_BUFFEREVENTS if (conn->bufev) { bufferevent_free(conn->bufev); conn->bufev = NULL; } #endif if (conn->type == CONN_TYPE_AP_DNS_LISTENER) { dnsserv_close_listener(conn); } } /** Remove the connection from the global list, and remove the * corresponding poll entry. Calling this function will shift the last * connection (if any) into the position occupied by conn. */ int connection_remove(connection_t *conn) { int current_index; connection_t *tmp; tor_assert(conn); log_debug(LD_NET,"removing socket %d (type %s), n_conns now %d", (int)conn->s, conn_type_to_string(conn->type), smartlist_len(connection_array)); control_event_conn_bandwidth(conn); tor_assert(conn->conn_array_index >= 0); current_index = conn->conn_array_index; connection_unregister_events(conn); /* This is redundant, but cheap. */ if (current_index == smartlist_len(connection_array)-1) { /* at the end */ smartlist_del(connection_array, current_index); return 0; } /* replace this one with the one at the end */ smartlist_del(connection_array, current_index); tmp = smartlist_get(connection_array, current_index); tmp->conn_array_index = current_index; return 0; } /** If conn is an edge conn, remove it from the list * of conn's on this circuit. If it's not on an edge, * flush and send destroys for all circuits on this conn. * * Remove it from connection_array (if applicable) and * from closeable_connection_list. * * Then free it. */ static void connection_unlink(connection_t *conn) { connection_about_to_close_connection(conn); if (conn->conn_array_index >= 0) { connection_remove(conn); } if (conn->linked_conn) { conn->linked_conn->linked_conn = NULL; if (! conn->linked_conn->marked_for_close && conn->linked_conn->reading_from_linked_conn) connection_start_reading(conn->linked_conn); conn->linked_conn = NULL; } smartlist_remove(closeable_connection_lst, conn); smartlist_remove(active_linked_connection_lst, conn); if (conn->type == CONN_TYPE_EXIT) { assert_connection_edge_not_dns_pending(TO_EDGE_CONN(conn)); } if (conn->type == CONN_TYPE_OR) { if (!tor_digest_is_zero(TO_OR_CONN(conn)->identity_digest)) connection_or_remove_from_identity_map(TO_OR_CONN(conn)); /* connection_unlink() can only get called if the connection * was already on the closeable list, and it got there by * connection_mark_for_close(), which was called from * connection_or_close_normally() or * connection_or_close_for_error(), so the channel should * already be in CHANNEL_STATE_CLOSING, and then the * connection_about_to_close_connection() goes to * connection_or_about_to_close(), which calls channel_closed() * to notify the channel_t layer, and closed the channel, so * nothing more to do here to deal with the channel associated * with an orconn. */ } connection_free(conn); } /** Initialize the global connection list, closeable connection list, * and active connection list. */ STATIC void init_connection_lists(void) { if (!connection_array) connection_array = smartlist_new(); if (!closeable_connection_lst) closeable_connection_lst = smartlist_new(); if (!active_linked_connection_lst) active_linked_connection_lst = smartlist_new(); } /** Schedule conn to be closed. **/ void add_connection_to_closeable_list(connection_t *conn) { tor_assert(!smartlist_contains(closeable_connection_lst, conn)); tor_assert(conn->marked_for_close); assert_connection_ok(conn, time(NULL)); smartlist_add(closeable_connection_lst, conn); } /** Return 1 if conn is on the closeable list, else return 0. */ int connection_is_on_closeable_list(connection_t *conn) { return smartlist_contains(closeable_connection_lst, conn); } /** Return true iff conn is in the current poll array. */ int connection_in_array(connection_t *conn) { return smartlist_contains(connection_array, conn); } /** Set *array to an array of all connections, and *n * to the length of the array. *array and *n must not * be modified. */ smartlist_t * get_connection_array(void) { if (!connection_array) connection_array = smartlist_new(); return connection_array; } /** Provides the traffic read and written over the life of the process. */ MOCK_IMPL(uint64_t, get_bytes_read,(void)) { return stats_n_bytes_read; } /* DOCDOC get_bytes_written */ MOCK_IMPL(uint64_t, get_bytes_written,(void)) { return stats_n_bytes_written; } /** Set the event mask on conn to events. (The event * mask is a bitmask whose bits are READ_EVENT and WRITE_EVENT) */ void connection_watch_events(connection_t *conn, watchable_events_t events) { IF_HAS_BUFFEREVENT(conn, { short ev = ((short)events) & (EV_READ|EV_WRITE); short old_ev = bufferevent_get_enabled(conn->bufev); if ((ev & ~old_ev) != 0) { bufferevent_enable(conn->bufev, ev); } if ((old_ev & ~ev) != 0) { bufferevent_disable(conn->bufev, old_ev & ~ev); } return; }); if (events & READ_EVENT) connection_start_reading(conn); else connection_stop_reading(conn); if (events & WRITE_EVENT) connection_start_writing(conn); else connection_stop_writing(conn); } /** Return true iff conn is listening for read events. */ int connection_is_reading(connection_t *conn) { tor_assert(conn); IF_HAS_BUFFEREVENT(conn, return (bufferevent_get_enabled(conn->bufev) & EV_READ) != 0; ); return conn->reading_from_linked_conn || (conn->read_event && event_pending(conn->read_event, EV_READ, NULL)); } /** Tell the main loop to stop notifying conn of any read events. */ MOCK_IMPL(void, connection_stop_reading,(connection_t *conn)) { tor_assert(conn); IF_HAS_BUFFEREVENT(conn, { bufferevent_disable(conn->bufev, EV_READ); return; }); tor_assert(conn->read_event); if (conn->linked) { conn->reading_from_linked_conn = 0; connection_stop_reading_from_linked_conn(conn); } else { if (event_del(conn->read_event)) log_warn(LD_NET, "Error from libevent setting read event state for %d " "to unwatched: %s", (int)conn->s, tor_socket_strerror(tor_socket_errno(conn->s))); } } /** Tell the main loop to start notifying conn of any read events. */ MOCK_IMPL(void, connection_start_reading,(connection_t *conn)) { tor_assert(conn); IF_HAS_BUFFEREVENT(conn, { bufferevent_enable(conn->bufev, EV_READ); return; }); tor_assert(conn->read_event); if (conn->linked) { conn->reading_from_linked_conn = 1; if (connection_should_read_from_linked_conn(conn)) connection_start_reading_from_linked_conn(conn); } else { if (event_add(conn->read_event, NULL)) log_warn(LD_NET, "Error from libevent setting read event state for %d " "to watched: %s", (int)conn->s, tor_socket_strerror(tor_socket_errno(conn->s))); } } /** Return true iff conn is listening for write events. */ int connection_is_writing(connection_t *conn) { tor_assert(conn); IF_HAS_BUFFEREVENT(conn, return (bufferevent_get_enabled(conn->bufev) & EV_WRITE) != 0; ); return conn->writing_to_linked_conn || (conn->write_event && event_pending(conn->write_event, EV_WRITE, NULL)); } /** Tell the main loop to stop notifying conn of any write events. */ MOCK_IMPL(void, connection_stop_writing,(connection_t *conn)) { tor_assert(conn); IF_HAS_BUFFEREVENT(conn, { bufferevent_disable(conn->bufev, EV_WRITE); return; }); tor_assert(conn->write_event); if (conn->linked) { conn->writing_to_linked_conn = 0; if (conn->linked_conn) connection_stop_reading_from_linked_conn(conn->linked_conn); } else { if (event_del(conn->write_event)) log_warn(LD_NET, "Error from libevent setting write event state for %d " "to unwatched: %s", (int)conn->s, tor_socket_strerror(tor_socket_errno(conn->s))); } } /** Tell the main loop to start notifying conn of any write events. */ MOCK_IMPL(void, connection_start_writing,(connection_t *conn)) { tor_assert(conn); IF_HAS_BUFFEREVENT(conn, { bufferevent_enable(conn->bufev, EV_WRITE); return; }); tor_assert(conn->write_event); if (conn->linked) { conn->writing_to_linked_conn = 1; if (conn->linked_conn && connection_should_read_from_linked_conn(conn->linked_conn)) connection_start_reading_from_linked_conn(conn->linked_conn); } else { if (event_add(conn->write_event, NULL)) log_warn(LD_NET, "Error from libevent setting write event state for %d " "to watched: %s", (int)conn->s, tor_socket_strerror(tor_socket_errno(conn->s))); } } /** Return true iff conn is linked conn, and reading from the conn * linked to it would be good and feasible. (Reading is "feasible" if the * other conn exists and has data in its outbuf, and is "good" if we have our * reading_from_linked_conn flag set and the other conn has its * writing_to_linked_conn flag set.)*/ static int connection_should_read_from_linked_conn(connection_t *conn) { if (conn->linked && conn->reading_from_linked_conn) { if (! conn->linked_conn || (conn->linked_conn->writing_to_linked_conn && buf_datalen(conn->linked_conn->outbuf))) return 1; } return 0; } /** Helper: Tell the main loop to begin reading bytes into conn from * its linked connection, if it is not doing so already. Called by * connection_start_reading and connection_start_writing as appropriate. */ static void connection_start_reading_from_linked_conn(connection_t *conn) { tor_assert(conn); tor_assert(conn->linked == 1); if (!conn->active_on_link) { conn->active_on_link = 1; smartlist_add(active_linked_connection_lst, conn); if (!called_loop_once) { /* This is the first event on the list; we won't be in LOOP_ONCE mode, * so we need to make sure that the event_base_loop() actually exits at * the end of its run through the current connections and lets us * activate read events for linked connections. */ struct timeval tv = { 0, 0 }; tor_event_base_loopexit(tor_libevent_get_base(), &tv); } } else { tor_assert(smartlist_contains(active_linked_connection_lst, conn)); } } /** Tell the main loop to stop reading bytes into conn from its linked * connection, if is currently doing so. Called by connection_stop_reading, * connection_stop_writing, and connection_read. */ void connection_stop_reading_from_linked_conn(connection_t *conn) { tor_assert(conn); tor_assert(conn->linked == 1); if (conn->active_on_link) { conn->active_on_link = 0; /* FFFF We could keep an index here so we can smartlist_del * cleanly. On the other hand, this doesn't show up on profiles, * so let's leave it alone for now. */ smartlist_remove(active_linked_connection_lst, conn); } else { tor_assert(!smartlist_contains(active_linked_connection_lst, conn)); } } /** Close all connections that have been scheduled to get closed. */ STATIC void close_closeable_connections(void) { int i; for (i = 0; i < smartlist_len(closeable_connection_lst); ) { connection_t *conn = smartlist_get(closeable_connection_lst, i); if (conn->conn_array_index < 0) { connection_unlink(conn); /* blow it away right now */ } else { if (!conn_close_if_marked(conn->conn_array_index)) ++i; } } } /** Libevent callback: this gets invoked when (connection_t*)conn has * some data to read. */ static void conn_read_callback(evutil_socket_t fd, short event, void *_conn) { connection_t *conn = _conn; (void)fd; (void)event; log_debug(LD_NET,"socket %d wants to read.",(int)conn->s); /* assert_connection_ok(conn, time(NULL)); */ if (connection_handle_read(conn) < 0) { if (!conn->marked_for_close) { #ifndef _WIN32 log_warn(LD_BUG,"Unhandled error on read for %s connection " "(fd %d); removing", conn_type_to_string(conn->type), (int)conn->s); tor_fragile_assert(); #endif if (CONN_IS_EDGE(conn)) connection_edge_end_errno(TO_EDGE_CONN(conn)); connection_mark_for_close(conn); } } assert_connection_ok(conn, time(NULL)); if (smartlist_len(closeable_connection_lst)) close_closeable_connections(); } /** Libevent callback: this gets invoked when (connection_t*)conn has * some data to write. */ static void conn_write_callback(evutil_socket_t fd, short events, void *_conn) { connection_t *conn = _conn; (void)fd; (void)events; LOG_FN_CONN(conn, (LOG_DEBUG, LD_NET, "socket %d wants to write.", (int)conn->s)); /* assert_connection_ok(conn, time(NULL)); */ if (connection_handle_write(conn, 0) < 0) { if (!conn->marked_for_close) { /* this connection is broken. remove it. */ log_fn(LOG_WARN,LD_BUG, "unhandled error on write for %s connection (fd %d); removing", conn_type_to_string(conn->type), (int)conn->s); tor_fragile_assert(); if (CONN_IS_EDGE(conn)) { /* otherwise we cry wolf about duplicate close */ edge_connection_t *edge_conn = TO_EDGE_CONN(conn); if (!edge_conn->end_reason) edge_conn->end_reason = END_STREAM_REASON_INTERNAL; edge_conn->edge_has_sent_end = 1; } connection_close_immediate(conn); /* So we don't try to flush. */ connection_mark_for_close(conn); } } assert_connection_ok(conn, time(NULL)); if (smartlist_len(closeable_connection_lst)) close_closeable_connections(); } /** If the connection at connection_array[i] is marked for close, then: * - If it has data that it wants to flush, try to flush it. * - If it _still_ has data to flush, and conn->hold_open_until_flushed is * true, then leave the connection open and return. * - Otherwise, remove the connection from connection_array and from * all other lists, close it, and free it. * Returns 1 if the connection was closed, 0 otherwise. */ static int conn_close_if_marked(int i) { connection_t *conn; int retval; time_t now; conn = smartlist_get(connection_array, i); if (!conn->marked_for_close) return 0; /* nothing to see here, move along */ now = time(NULL); assert_connection_ok(conn, now); /* assert_all_pending_dns_resolves_ok(); */ #ifdef USE_BUFFEREVENTS if (conn->bufev) { if (conn->hold_open_until_flushed && evbuffer_get_length(bufferevent_get_output(conn->bufev))) { /* don't close yet. */ return 0; } if (conn->linked_conn && ! conn->linked_conn->marked_for_close) { /* We need to do this explicitly so that the linked connection * notices that there was an EOF. */ bufferevent_flush(conn->bufev, EV_WRITE, BEV_FINISHED); } } #endif log_debug(LD_NET,"Cleaning up connection (fd "TOR_SOCKET_T_FORMAT").", conn->s); /* If the connection we are about to close was trying to connect to a proxy server and failed, the client won't be able to use that proxy. We should warn the user about this. */ if (conn->proxy_state == PROXY_INFANT) log_failed_proxy_connection(conn); IF_HAS_BUFFEREVENT(conn, goto unlink); if ((SOCKET_OK(conn->s) || conn->linked_conn) && connection_wants_to_flush(conn)) { /* s == -1 means it's an incomplete edge connection, or that the socket * has already been closed as unflushable. */ ssize_t sz = connection_bucket_write_limit(conn, now); if (!conn->hold_open_until_flushed) log_info(LD_NET, "Conn (addr %s, fd %d, type %s, state %d) marked, but wants " "to flush %d bytes. (Marked at %s:%d)", escaped_safe_str_client(conn->address), (int)conn->s, conn_type_to_string(conn->type), conn->state, (int)conn->outbuf_flushlen, conn->marked_for_close_file, conn->marked_for_close); if (conn->linked_conn) { retval = move_buf_to_buf(conn->linked_conn->inbuf, conn->outbuf, &conn->outbuf_flushlen); if (retval >= 0) { /* The linked conn will notice that it has data when it notices that * we're gone. */ connection_start_reading_from_linked_conn(conn->linked_conn); } log_debug(LD_GENERAL, "Flushed last %d bytes from a linked conn; " "%d left; flushlen %d; wants-to-flush==%d", retval, (int)connection_get_outbuf_len(conn), (int)conn->outbuf_flushlen, connection_wants_to_flush(conn)); } else if (connection_speaks_cells(conn)) { if (conn->state == OR_CONN_STATE_OPEN) { retval = flush_buf_tls(TO_OR_CONN(conn)->tls, conn->outbuf, sz, &conn->outbuf_flushlen); } else retval = -1; /* never flush non-open broken tls connections */ } else { retval = flush_buf(conn->s, conn->outbuf, sz, &conn->outbuf_flushlen); } if (retval >= 0 && /* Technically, we could survive things like TLS_WANT_WRITE here. But don't bother for now. */ conn->hold_open_until_flushed && connection_wants_to_flush(conn)) { if (retval > 0) { LOG_FN_CONN(conn, (LOG_INFO,LD_NET, "Holding conn (fd %d) open for more flushing.", (int)conn->s)); conn->timestamp_lastwritten = now; /* reset so we can flush more */ } else if (sz == 0) { /* Also, retval==0. If we get here, we didn't want to write anything * (because of rate-limiting) and we didn't. */ /* Connection must flush before closing, but it's being rate-limited. * Let's remove from Libevent, and mark it as blocked on bandwidth * so it will be re-added on next token bucket refill. Prevents * busy Libevent loops where we keep ending up here and returning * 0 until we are no longer blocked on bandwidth. */ if (connection_is_writing(conn)) { conn->write_blocked_on_bw = 1; connection_stop_writing(conn); } if (connection_is_reading(conn)) { /* XXXX024 We should make this code unreachable; if a connection is * marked for close and flushing, there is no point in reading to it * at all. Further, checking at this point is a bit of a hack: it * would make much more sense to react in * connection_handle_read_impl, or to just stop reading in * mark_and_flush */ #if 0 #define MARKED_READING_RATE 180 static ratelim_t marked_read_lim = RATELIM_INIT(MARKED_READING_RATE); char *m; if ((m = rate_limit_log(&marked_read_lim, now))) { log_warn(LD_BUG, "Marked connection (fd %d, type %s, state %s) " "is still reading; that shouldn't happen.%s", (int)conn->s, conn_type_to_string(conn->type), conn_state_to_string(conn->type, conn->state), m); tor_free(m); } #endif conn->read_blocked_on_bw = 1; connection_stop_reading(conn); } } return 0; } if (connection_wants_to_flush(conn)) { log_fn(LOG_INFO, LD_NET, "We stalled too much while trying to write %d " "bytes to address %s. If this happens a lot, either " "something is wrong with your network connection, or " "something is wrong with theirs. " "(fd %d, type %s, state %d, marked at %s:%d).", (int)connection_get_outbuf_len(conn), escaped_safe_str_client(conn->address), (int)conn->s, conn_type_to_string(conn->type), conn->state, conn->marked_for_close_file, conn->marked_for_close); } } #ifdef USE_BUFFEREVENTS unlink: #endif connection_unlink(conn); /* unlink, remove, free */ return 1; } /** We've just tried every dirserver we know about, and none of * them were reachable. Assume the network is down. Change state * so next time an application connection arrives we'll delay it * and try another directory fetch. Kill off all the circuit_wait * streams that are waiting now, since they will all timeout anyway. */ void directory_all_unreachable(time_t now) { connection_t *conn; (void)now; stats_n_seconds_working=0; /* reset it */ while ((conn = connection_get_by_type_state(CONN_TYPE_AP, AP_CONN_STATE_CIRCUIT_WAIT))) { entry_connection_t *entry_conn = TO_ENTRY_CONN(conn); log_notice(LD_NET, "Is your network connection down? " "Failing connection to '%s:%d'.", safe_str_client(entry_conn->socks_request->address), entry_conn->socks_request->port); connection_mark_unattached_ap(entry_conn, END_STREAM_REASON_NET_UNREACHABLE); } control_event_general_status(LOG_ERR, "DIR_ALL_UNREACHABLE"); } /** This function is called whenever we successfully pull down some new * network statuses or server descriptors. */ void directory_info_has_arrived(time_t now, int from_cache) { const or_options_t *options = get_options(); if (!router_have_minimum_dir_info()) { int quiet = from_cache || directory_too_idle_to_fetch_descriptors(options, now); tor_log(quiet ? LOG_INFO : LOG_NOTICE, LD_DIR, "I learned some more directory information, but not enough to " "build a circuit: %s", get_dir_info_status_string()); update_all_descriptor_downloads(now); return; } else { if (directory_fetches_from_authorities(options)) { update_all_descriptor_downloads(now); } /* if we have enough dir info, then update our guard status with * whatever we just learned. */ entry_guards_compute_status(options, now); /* Don't even bother trying to get extrainfo until the rest of our * directory info is up-to-date */ if (options->DownloadExtraInfo) update_extrainfo_downloads(now); } if (server_mode(options) && !net_is_disabled() && !from_cache && (can_complete_circuit || !any_predicted_circuits(now))) consider_testing_reachability(1, 1); } /** How long do we wait before killing OR connections with no circuits? * In Tor versions up to 0.2.1.25 and 0.2.2.12-alpha, we waited 15 minutes * before cancelling these connections, which caused fast relays to accrue * many many idle connections. Hopefully 3 minutes is low enough that * it kills most idle connections, without being so low that we cause * clients to bounce on and off. */ #define IDLE_OR_CONN_TIMEOUT 180 /** Perform regular maintenance tasks for a single connection. This * function gets run once per second per connection by run_scheduled_events. */ static void run_connection_housekeeping(int i, time_t now) { cell_t cell; connection_t *conn = smartlist_get(connection_array, i); const or_options_t *options = get_options(); or_connection_t *or_conn; int past_keepalive = now >= conn->timestamp_lastwritten + options->KeepalivePeriod; if (conn->outbuf && !connection_get_outbuf_len(conn) && conn->type == CONN_TYPE_OR) TO_OR_CONN(conn)->timestamp_lastempty = now; if (conn->marked_for_close) { /* nothing to do here */ return; } /* Expire any directory connections that haven't been active (sent * if a server or received if a client) for 5 min */ if (conn->type == CONN_TYPE_DIR && ((DIR_CONN_IS_SERVER(conn) && conn->timestamp_lastwritten + options->TestingDirConnectionMaxStall < now) || (!DIR_CONN_IS_SERVER(conn) && conn->timestamp_lastread + options->TestingDirConnectionMaxStall < now))) { log_info(LD_DIR,"Expiring wedged directory conn (fd %d, purpose %d)", (int)conn->s, conn->purpose); /* This check is temporary; it's to let us know whether we should consider * parsing partial serverdesc responses. */ if (conn->purpose == DIR_PURPOSE_FETCH_SERVERDESC && connection_get_inbuf_len(conn) >= 1024) { log_info(LD_DIR,"Trying to extract information from wedged server desc " "download."); connection_dir_reached_eof(TO_DIR_CONN(conn)); } else { connection_mark_for_close(conn); } return; } if (!connection_speaks_cells(conn)) return; /* we're all done here, the rest is just for OR conns */ /* If we haven't written to an OR connection for a while, then either nuke the connection or send a keepalive, depending. */ or_conn = TO_OR_CONN(conn); #ifdef USE_BUFFEREVENTS tor_assert(conn->bufev); #else tor_assert(conn->outbuf); #endif if (channel_is_bad_for_new_circs(TLS_CHAN_TO_BASE(or_conn->chan)) && !connection_or_get_num_circuits(or_conn)) { /* It's bad for new circuits, and has no unmarked circuits on it: * mark it now. */ log_info(LD_OR, "Expiring non-used OR connection to fd %d (%s:%d) [Too old].", (int)conn->s, conn->address, conn->port); if (conn->state == OR_CONN_STATE_CONNECTING) connection_or_connect_failed(TO_OR_CONN(conn), END_OR_CONN_REASON_TIMEOUT, "Tor gave up on the connection"); connection_or_close_normally(TO_OR_CONN(conn), 1); } else if (!connection_state_is_open(conn)) { if (past_keepalive) { /* We never managed to actually get this connection open and happy. */ log_info(LD_OR,"Expiring non-open OR connection to fd %d (%s:%d).", (int)conn->s,conn->address, conn->port); connection_or_close_normally(TO_OR_CONN(conn), 0); } } else if (we_are_hibernating() && !connection_or_get_num_circuits(or_conn) && !connection_get_outbuf_len(conn)) { /* We're hibernating, there's no circuits, and nothing to flush.*/ log_info(LD_OR,"Expiring non-used OR connection to fd %d (%s:%d) " "[Hibernating or exiting].", (int)conn->s,conn->address, conn->port); connection_or_close_normally(TO_OR_CONN(conn), 1); } else if (!connection_or_get_num_circuits(or_conn) && now >= or_conn->timestamp_last_added_nonpadding + IDLE_OR_CONN_TIMEOUT) { log_info(LD_OR,"Expiring non-used OR connection to fd %d (%s:%d) " "[idle %d].", (int)conn->s,conn->address, conn->port, (int)(now - or_conn->timestamp_last_added_nonpadding)); connection_or_close_normally(TO_OR_CONN(conn), 0); } else if ( now >= or_conn->timestamp_lastempty + options->KeepalivePeriod*10 && now >= conn->timestamp_lastwritten + options->KeepalivePeriod*10) { log_fn(LOG_PROTOCOL_WARN,LD_PROTOCOL, "Expiring stuck OR connection to fd %d (%s:%d). (%d bytes to " "flush; %d seconds since last write)", (int)conn->s, conn->address, conn->port, (int)connection_get_outbuf_len(conn), (int)(now-conn->timestamp_lastwritten)); connection_or_close_normally(TO_OR_CONN(conn), 0); } else if (past_keepalive && !connection_get_outbuf_len(conn)) { /* send a padding cell */ log_fn(LOG_DEBUG,LD_OR,"Sending keepalive to (%s:%d)", conn->address, conn->port); memset(&cell,0,sizeof(cell_t)); cell.command = CELL_PADDING; connection_or_write_cell_to_buf(&cell, or_conn); } } /** Honor a NEWNYM request: make future requests unlinkable to past * requests. */ static void signewnym_impl(time_t now) { const or_options_t *options = get_options(); if (!proxy_mode(options)) { log_info(LD_CONTROL, "Ignoring SIGNAL NEWNYM because client functionality " "is disabled."); return; } circuit_mark_all_dirty_circs_as_unusable(); addressmap_clear_transient(); rend_client_purge_state(); time_of_last_signewnym = now; signewnym_is_pending = 0; ++newnym_epoch; control_event_signal(SIGNEWNYM); } /** Return the number of times that signewnym has been called. */ unsigned get_signewnym_epoch(void) { return newnym_epoch; } static time_t time_to_check_descriptor = 0; /** * Update our schedule so that we'll check whether we need to update our * descriptor immediately, rather than after up to CHECK_DESCRIPTOR_INTERVAL * seconds. */ void reschedule_descriptor_update_check(void) { time_to_check_descriptor = 0; } /** Perform regular maintenance tasks. This function gets run once per * second by second_elapsed_callback(). */ static void run_scheduled_events(time_t now) { static time_t last_rotated_x509_certificate = 0; static time_t time_to_check_v3_certificate = 0; static time_t time_to_check_listeners = 0; static time_t time_to_download_networkstatus = 0; static time_t time_to_shrink_memory = 0; static time_t time_to_try_getting_descriptors = 0; static time_t time_to_reset_descriptor_failures = 0; static time_t time_to_add_entropy = 0; static time_t time_to_write_bridge_status_file = 0; static time_t time_to_downrate_stability = 0; static time_t time_to_save_stability = 0; static time_t time_to_clean_caches = 0; static time_t time_to_recheck_bandwidth = 0; static time_t time_to_check_for_expired_networkstatus = 0; static time_t time_to_write_stats_files = 0; static time_t time_to_write_bridge_stats = 0; static time_t time_to_check_port_forwarding = 0; static time_t time_to_launch_reachability_tests = 0; static int should_init_bridge_stats = 1; static time_t time_to_retry_dns_init = 0; static time_t time_to_next_heartbeat = 0; const or_options_t *options = get_options(); int is_server = server_mode(options); int i; int have_dir_info; /* 0. See if we've been asked to shut down and our timeout has * expired; or if our bandwidth limits are exhausted and we * should hibernate; or if it's time to wake up from hibernation. */ consider_hibernation(now); /* 0b. If we've deferred a signewnym, make sure it gets handled * eventually. */ if (signewnym_is_pending && time_of_last_signewnym + MAX_SIGNEWNYM_RATE <= now) { log_info(LD_CONTROL, "Honoring delayed NEWNYM request"); signewnym_impl(now); } /* 0c. If we've deferred log messages for the controller, handle them now */ flush_pending_log_callbacks(); /* 1a. Every MIN_ONION_KEY_LIFETIME seconds, rotate the onion keys, * shut down and restart all cpuworkers, and update the directory if * necessary. */ if (is_server && get_onion_key_set_at()+MIN_ONION_KEY_LIFETIME < now) { log_info(LD_GENERAL,"Rotating onion key."); rotate_onion_key(); cpuworkers_rotate(); if (router_rebuild_descriptor(1)<0) { log_info(LD_CONFIG, "Couldn't rebuild router descriptor"); } if (advertised_server_mode() && !options->DisableNetwork) router_upload_dir_desc_to_dirservers(0); } if (!should_delay_dir_fetches(options, NULL) && time_to_try_getting_descriptors < now) { update_all_descriptor_downloads(now); update_extrainfo_downloads(now); if (router_have_minimum_dir_info()) time_to_try_getting_descriptors = now + LAZY_DESCRIPTOR_RETRY_INTERVAL; else time_to_try_getting_descriptors = now + GREEDY_DESCRIPTOR_RETRY_INTERVAL; } if (time_to_reset_descriptor_failures < now) { router_reset_descriptor_download_failures(); time_to_reset_descriptor_failures = now + DESCRIPTOR_FAILURE_RESET_INTERVAL; } if (options->UseBridges) fetch_bridge_descriptors(options, now); /* 1b. Every MAX_SSL_KEY_LIFETIME_INTERNAL seconds, we change our * TLS context. */ if (!last_rotated_x509_certificate) last_rotated_x509_certificate = now; if (last_rotated_x509_certificate+MAX_SSL_KEY_LIFETIME_INTERNAL < now) { log_info(LD_GENERAL,"Rotating tls context."); if (router_initialize_tls_context() < 0) { log_warn(LD_BUG, "Error reinitializing TLS context"); /* XXX is it a bug here, that we just keep going? -RD */ } last_rotated_x509_certificate = now; /* We also make sure to rotate the TLS connections themselves if they've * been up for too long -- but that's done via is_bad_for_new_circs in * connection_run_housekeeping() above. */ } if (time_to_add_entropy < now) { if (time_to_add_entropy) { /* We already seeded once, so don't die on failure. */ crypto_seed_rng(0); } /** How often do we add more entropy to OpenSSL's RNG pool? */ #define ENTROPY_INTERVAL (60*60) time_to_add_entropy = now + ENTROPY_INTERVAL; } /* 1c. If we have to change the accounting interval or record * bandwidth used in this accounting interval, do so. */ if (accounting_is_enabled(options)) accounting_run_housekeeping(now); if (time_to_launch_reachability_tests < now && (authdir_mode_tests_reachability(options)) && !net_is_disabled()) { time_to_launch_reachability_tests = now + REACHABILITY_TEST_INTERVAL; /* try to determine reachability of the other Tor relays */ dirserv_test_reachability(now); } /* 1d. Periodically, we discount older stability information so that new * stability info counts more, and save the stability information to disk as * appropriate. */ if (time_to_downrate_stability < now) time_to_downrate_stability = rep_hist_downrate_old_runs(now); if (authdir_mode_tests_reachability(options)) { if (time_to_save_stability < now) { if (time_to_save_stability && rep_hist_record_mtbf_data(now, 1)<0) { log_warn(LD_GENERAL, "Couldn't store mtbf data."); } #define SAVE_STABILITY_INTERVAL (30*60) time_to_save_stability = now + SAVE_STABILITY_INTERVAL; } } /* 1e. Periodically, if we're a v3 authority, we check whether our cert is * close to expiring and warn the admin if it is. */ if (time_to_check_v3_certificate < now) { v3_authority_check_key_expiry(); #define CHECK_V3_CERTIFICATE_INTERVAL (5*60) time_to_check_v3_certificate = now + CHECK_V3_CERTIFICATE_INTERVAL; } /* 1f. Check whether our networkstatus has expired. */ if (time_to_check_for_expired_networkstatus < now) { networkstatus_t *ns = networkstatus_get_latest_consensus(); /*XXXX RD: This value needs to be the same as REASONABLY_LIVE_TIME in * networkstatus_get_reasonably_live_consensus(), but that value is way * way too high. Arma: is the bridge issue there resolved yet? -NM */ #define NS_EXPIRY_SLOP (24*60*60) if (ns && ns->valid_until < now+NS_EXPIRY_SLOP && router_have_minimum_dir_info()) { router_dir_info_changed(); } #define CHECK_EXPIRED_NS_INTERVAL (2*60) time_to_check_for_expired_networkstatus = now + CHECK_EXPIRED_NS_INTERVAL; } /* 1g. Check whether we should write statistics to disk. */ if (time_to_write_stats_files < now) { #define CHECK_WRITE_STATS_INTERVAL (60*60) time_t next_time_to_write_stats_files = (time_to_write_stats_files > 0 ? time_to_write_stats_files : now) + CHECK_WRITE_STATS_INTERVAL; if (options->CellStatistics) { time_t next_write = rep_hist_buffer_stats_write(time_to_write_stats_files); if (next_write && next_write < next_time_to_write_stats_files) next_time_to_write_stats_files = next_write; } if (options->DirReqStatistics) { time_t next_write = geoip_dirreq_stats_write(time_to_write_stats_files); if (next_write && next_write < next_time_to_write_stats_files) next_time_to_write_stats_files = next_write; } if (options->EntryStatistics) { time_t next_write = geoip_entry_stats_write(time_to_write_stats_files); if (next_write && next_write < next_time_to_write_stats_files) next_time_to_write_stats_files = next_write; } if (options->ExitPortStatistics) { time_t next_write = rep_hist_exit_stats_write(time_to_write_stats_files); if (next_write && next_write < next_time_to_write_stats_files) next_time_to_write_stats_files = next_write; } if (options->ConnDirectionStatistics) { time_t next_write = rep_hist_conn_stats_write(time_to_write_stats_files); if (next_write && next_write < next_time_to_write_stats_files) next_time_to_write_stats_files = next_write; } if (options->BridgeAuthoritativeDir) { time_t next_write = rep_hist_desc_stats_write(time_to_write_stats_files); if (next_write && next_write < next_time_to_write_stats_files) next_time_to_write_stats_files = next_write; } time_to_write_stats_files = next_time_to_write_stats_files; } /* 1h. Check whether we should write bridge statistics to disk. */ if (should_record_bridge_info(options)) { if (time_to_write_bridge_stats < now) { if (should_init_bridge_stats) { /* (Re-)initialize bridge statistics. */ geoip_bridge_stats_init(now); time_to_write_bridge_stats = now + WRITE_STATS_INTERVAL; should_init_bridge_stats = 0; } else { /* Possibly write bridge statistics to disk and ask when to write * them next time. */ time_to_write_bridge_stats = geoip_bridge_stats_write( time_to_write_bridge_stats); } } } else if (!should_init_bridge_stats) { /* Bridge mode was turned off. Ensure that stats are re-initialized * next time bridge mode is turned on. */ should_init_bridge_stats = 1; } /* Remove old information from rephist and the rend cache. */ if (time_to_clean_caches < now) { rep_history_clean(now - options->RephistTrackTime); rend_cache_clean(now); rend_cache_clean_v2_descs_as_dir(now); microdesc_cache_rebuild(NULL, 0); #define CLEAN_CACHES_INTERVAL (30*60) time_to_clean_caches = now + CLEAN_CACHES_INTERVAL; } #define RETRY_DNS_INTERVAL (10*60) /* If we're a server and initializing dns failed, retry periodically. */ if (time_to_retry_dns_init < now) { time_to_retry_dns_init = now + RETRY_DNS_INTERVAL; if (is_server && has_dns_init_failed()) dns_init(); } /* 2. Periodically, we consider force-uploading our descriptor * (if we've passed our internal checks). */ /** How often do we check whether part of our router info has changed in a * way that would require an upload? That includes checking whether our IP * address has changed. */ #define CHECK_DESCRIPTOR_INTERVAL (60) /* 2b. Once per minute, regenerate and upload the descriptor if the old * one is inaccurate. */ if (time_to_check_descriptor < now && !options->DisableNetwork) { static int dirport_reachability_count = 0; time_to_check_descriptor = now + CHECK_DESCRIPTOR_INTERVAL; check_descriptor_bandwidth_changed(now); check_descriptor_ipaddress_changed(now); mark_my_descriptor_dirty_if_too_old(now); consider_publishable_server(0); /* also, check religiously for reachability, if it's within the first * 20 minutes of our uptime. */ if (is_server && (can_complete_circuit || !any_predicted_circuits(now)) && !we_are_hibernating()) { if (stats_n_seconds_working < TIMEOUT_UNTIL_UNREACHABILITY_COMPLAINT) { consider_testing_reachability(1, dirport_reachability_count==0); if (++dirport_reachability_count > 5) dirport_reachability_count = 0; } else if (time_to_recheck_bandwidth < now) { /* If we haven't checked for 12 hours and our bandwidth estimate is * low, do another bandwidth test. This is especially important for * bridges, since they might go long periods without much use. */ const routerinfo_t *me = router_get_my_routerinfo(); if (time_to_recheck_bandwidth && me && me->bandwidthcapacity < me->bandwidthrate && me->bandwidthcapacity < 51200) { reset_bandwidth_test(); } #define BANDWIDTH_RECHECK_INTERVAL (12*60*60) time_to_recheck_bandwidth = now + BANDWIDTH_RECHECK_INTERVAL; } } /* If any networkstatus documents are no longer recent, we need to * update all the descriptors' running status. */ /* Remove dead routers. */ routerlist_remove_old_routers(); } /* 2c. Every minute (or every second if TestingTorNetwork), check * whether we want to download any networkstatus documents. */ /* How often do we check whether we should download network status * documents? */ #define networkstatus_dl_check_interval(o) ((o)->TestingTorNetwork ? 1 : 60) if (!should_delay_dir_fetches(options, NULL) && time_to_download_networkstatus < now) { time_to_download_networkstatus = now + networkstatus_dl_check_interval(options); update_networkstatus_downloads(now); } /* 2c. Let directory voting happen. */ if (authdir_mode_v3(options)) dirvote_act(options, now); /* 3a. Every second, we examine pending circuits and prune the * ones which have been pending for more than a few seconds. * We do this before step 4, so it can try building more if * it's not comfortable with the number of available circuits. */ /* (If our circuit build timeout can ever become lower than a second (which * it can't, currently), we should do this more often.) */ circuit_expire_building(); /* 3b. Also look at pending streams and prune the ones that 'began' * a long time ago but haven't gotten a 'connected' yet. * Do this before step 4, so we can put them back into pending * state to be picked up by the new circuit. */ connection_ap_expire_beginning(); /* 3c. And expire connections that we've held open for too long. */ connection_expire_held_open(); /* 3d. And every 60 seconds, we relaunch listeners if any died. */ if (!net_is_disabled() && time_to_check_listeners < now) { retry_all_listeners(NULL, NULL, 0); time_to_check_listeners = now+60; } /* 4. Every second, we try a new circuit if there are no valid * circuits. Every NewCircuitPeriod seconds, we expire circuits * that became dirty more than MaxCircuitDirtiness seconds ago, * and we make a new circ if there are no clean circuits. */ have_dir_info = router_have_minimum_dir_info(); if (have_dir_info && !net_is_disabled()) circuit_build_needed_circs(now); /* every 10 seconds, but not at the same second as other such events */ if (now % 10 == 5) circuit_expire_old_circuits_serverside(now); /* 5. We do housekeeping for each connection... */ connection_or_set_bad_connections(NULL, 0); for (i=0;ioutbuf) buf_shrink(conn->outbuf); if (conn->inbuf) buf_shrink(conn->inbuf); }); #ifdef ENABLE_MEMPOOL clean_cell_pool(); #endif /* ENABLE_MEMPOOL */ buf_shrink_freelists(0); /** How often do we check buffers and pools for empty space that can be * deallocated? */ #define MEM_SHRINK_INTERVAL (60) time_to_shrink_memory = now + MEM_SHRINK_INTERVAL; } /* 6. And remove any marked circuits... */ circuit_close_all_marked(); /* 7. And upload service descriptors if necessary. */ if (can_complete_circuit && !net_is_disabled()) { rend_consider_services_upload(now); rend_consider_descriptor_republication(); } /* 8. and blow away any connections that need to die. have to do this now, * because if we marked a conn for close and left its socket -1, then * we'll pass it to poll/select and bad things will happen. */ close_closeable_connections(); /* 8b. And if anything in our state is ready to get flushed to disk, we * flush it. */ or_state_save(now); /* 8c. Do channel cleanup just like for connections */ channel_run_cleanup(); channel_listener_run_cleanup(); /* 9. and if we're an exit node, check whether our DNS is telling stories * to us. */ if (!net_is_disabled() && public_server_mode(options) && time_to_check_for_correct_dns < now && ! router_my_exit_policy_is_reject_star()) { if (!time_to_check_for_correct_dns) { time_to_check_for_correct_dns = now + 60 + crypto_rand_int(120); } else { dns_launch_correctness_checks(); time_to_check_for_correct_dns = now + 12*3600 + crypto_rand_int(12*3600); } } /* 10. write bridge networkstatus file to disk */ if (options->BridgeAuthoritativeDir && time_to_write_bridge_status_file < now) { networkstatus_dump_bridge_status_to_file(now); #define BRIDGE_STATUSFILE_INTERVAL (30*60) time_to_write_bridge_status_file = now+BRIDGE_STATUSFILE_INTERVAL; } /* 11. check the port forwarding app */ if (!net_is_disabled() && time_to_check_port_forwarding < now && options->PortForwarding && is_server) { #define PORT_FORWARDING_CHECK_INTERVAL 5 smartlist_t *ports_to_forward = get_list_of_ports_to_forward(); if (ports_to_forward) { tor_check_port_forwarding(options->PortForwardingHelper, ports_to_forward, now); SMARTLIST_FOREACH(ports_to_forward, char *, cp, tor_free(cp)); smartlist_free(ports_to_forward); } time_to_check_port_forwarding = now+PORT_FORWARDING_CHECK_INTERVAL; } /* 11b. check pending unconfigured managed proxies */ if (!net_is_disabled() && pt_proxies_configuration_pending()) pt_configure_remaining_proxies(); /* 12. write the heartbeat message */ if (options->HeartbeatPeriod && time_to_next_heartbeat <= now) { if (time_to_next_heartbeat) /* don't log the first heartbeat */ log_heartbeat(now); time_to_next_heartbeat = now+options->HeartbeatPeriod; } } /** Timer: used to invoke second_elapsed_callback() once per second. */ static periodic_timer_t *second_timer = NULL; /** Number of libevent errors in the last second: we die if we get too many. */ static int n_libevent_errors = 0; /** Libevent callback: invoked once every second. */ static void second_elapsed_callback(periodic_timer_t *timer, void *arg) { /* XXXX This could be sensibly refactored into multiple callbacks, and we * could use Libevent's timers for this rather than checking the current * time against a bunch of timeouts every second. */ static time_t current_second = 0; time_t now; size_t bytes_written; size_t bytes_read; int seconds_elapsed; const or_options_t *options = get_options(); (void)timer; (void)arg; n_libevent_errors = 0; /* log_notice(LD_GENERAL, "Tick."); */ now = time(NULL); update_approx_time(now); /* the second has rolled over. check more stuff. */ seconds_elapsed = current_second ? (int)(now - current_second) : 0; #ifdef USE_BUFFEREVENTS { uint64_t cur_read,cur_written; connection_get_rate_limit_totals(&cur_read, &cur_written); bytes_written = (size_t)(cur_written - stats_prev_n_written); bytes_read = (size_t)(cur_read - stats_prev_n_read); stats_n_bytes_read += bytes_read; stats_n_bytes_written += bytes_written; if (accounting_is_enabled(options) && seconds_elapsed >= 0) accounting_add_bytes(bytes_read, bytes_written, seconds_elapsed); stats_prev_n_written = cur_written; stats_prev_n_read = cur_read; } #else bytes_read = (size_t)(stats_n_bytes_read - stats_prev_n_read); bytes_written = (size_t)(stats_n_bytes_written - stats_prev_n_written); stats_prev_n_read = stats_n_bytes_read; stats_prev_n_written = stats_n_bytes_written; #endif control_event_bandwidth_used((uint32_t)bytes_read,(uint32_t)bytes_written); control_event_stream_bandwidth_used(); control_event_conn_bandwidth_used(); control_event_circ_bandwidth_used(); control_event_circuit_cell_stats(); if (server_mode(options) && !net_is_disabled() && seconds_elapsed > 0 && can_complete_circuit && stats_n_seconds_working / TIMEOUT_UNTIL_UNREACHABILITY_COMPLAINT != (stats_n_seconds_working+seconds_elapsed) / TIMEOUT_UNTIL_UNREACHABILITY_COMPLAINT) { /* every 20 minutes, check and complain if necessary */ const routerinfo_t *me = router_get_my_routerinfo(); if (me && !check_whether_orport_reachable()) { char *address = tor_dup_ip(me->addr); log_warn(LD_CONFIG,"Your server (%s:%d) has not managed to confirm that " "its ORPort is reachable. Please check your firewalls, ports, " "address, /etc/hosts file, etc.", address, me->or_port); control_event_server_status(LOG_WARN, "REACHABILITY_FAILED ORADDRESS=%s:%d", address, me->or_port); tor_free(address); } if (me && !check_whether_dirport_reachable()) { char *address = tor_dup_ip(me->addr); log_warn(LD_CONFIG, "Your server (%s:%d) has not managed to confirm that its " "DirPort is reachable. Please check your firewalls, ports, " "address, /etc/hosts file, etc.", address, me->dir_port); control_event_server_status(LOG_WARN, "REACHABILITY_FAILED DIRADDRESS=%s:%d", address, me->dir_port); tor_free(address); } } /** If more than this many seconds have elapsed, probably the clock * jumped: doesn't count. */ #define NUM_JUMPED_SECONDS_BEFORE_WARN 100 if (seconds_elapsed < -NUM_JUMPED_SECONDS_BEFORE_WARN || seconds_elapsed >= NUM_JUMPED_SECONDS_BEFORE_WARN) { circuit_note_clock_jumped(seconds_elapsed); /* XXX if the time jumps *back* many months, do our events in * run_scheduled_events() recover? I don't think they do. -RD */ } else if (seconds_elapsed > 0) stats_n_seconds_working += seconds_elapsed; run_scheduled_events(now); current_second = now; /* remember which second it is, for next time */ } #ifndef USE_BUFFEREVENTS /** Timer: used to invoke refill_callback(). */ static periodic_timer_t *refill_timer = NULL; /** Libevent callback: invoked periodically to refill token buckets * and count r/w bytes. It is only used when bufferevents are disabled. */ static void refill_callback(periodic_timer_t *timer, void *arg) { static struct timeval current_millisecond; struct timeval now; size_t bytes_written; size_t bytes_read; int milliseconds_elapsed = 0; int seconds_rolled_over = 0; const or_options_t *options = get_options(); (void)timer; (void)arg; tor_gettimeofday(&now); /* If this is our first time, no time has passed. */ if (current_millisecond.tv_sec) { long mdiff = tv_mdiff(¤t_millisecond, &now); if (mdiff > INT_MAX) mdiff = INT_MAX; milliseconds_elapsed = (int)mdiff; seconds_rolled_over = (int)(now.tv_sec - current_millisecond.tv_sec); } bytes_written = stats_prev_global_write_bucket - global_write_bucket; bytes_read = stats_prev_global_read_bucket - global_read_bucket; stats_n_bytes_read += bytes_read; stats_n_bytes_written += bytes_written; if (accounting_is_enabled(options) && milliseconds_elapsed >= 0) accounting_add_bytes(bytes_read, bytes_written, seconds_rolled_over); if (milliseconds_elapsed > 0) connection_bucket_refill(milliseconds_elapsed, (time_t)now.tv_sec); stats_prev_global_read_bucket = global_read_bucket; stats_prev_global_write_bucket = global_write_bucket; current_millisecond = now; /* remember what time it is, for next time */ } #endif #ifndef _WIN32 /** Called when a possibly ignorable libevent error occurs; ensures that we * don't get into an infinite loop by ignoring too many errors from * libevent. */ static int got_libevent_error(void) { if (++n_libevent_errors > 8) { log_err(LD_NET, "Too many libevent errors in one second; dying"); return -1; } return 0; } #endif #define UPTIME_CUTOFF_FOR_NEW_BANDWIDTH_TEST (6*60*60) /** Called when our IP address seems to have changed. at_interface * should be true if we detected a change in our interface, and false if we * detected a change in our published address. */ void ip_address_changed(int at_interface) { int server = server_mode(get_options()); if (at_interface) { if (! server) { /* Okay, change our keys. */ if (init_keys()<0) log_warn(LD_GENERAL, "Unable to rotate keys after IP change!"); } } else { if (server) { if (stats_n_seconds_working > UPTIME_CUTOFF_FOR_NEW_BANDWIDTH_TEST) reset_bandwidth_test(); stats_n_seconds_working = 0; router_reset_reachability(); mark_my_descriptor_dirty("IP address changed"); } } dns_servers_relaunch_checks(); } /** Forget what we've learned about the correctness of our DNS servers, and * start learning again. */ void dns_servers_relaunch_checks(void) { if (server_mode(get_options())) { dns_reset_correctness_checks(); time_to_check_for_correct_dns = 0; } } /** Called when we get a SIGHUP: reload configuration files and keys, * retry all connections, and so on. */ static int do_hup(void) { const or_options_t *options = get_options(); #ifdef USE_DMALLOC dmalloc_log_stats(); dmalloc_log_changed(0, 1, 0, 0); #endif log_notice(LD_GENERAL,"Received reload signal (hup). Reloading config and " "resetting internal state."); if (accounting_is_enabled(options)) accounting_record_bandwidth_usage(time(NULL), get_or_state()); router_reset_warnings(); routerlist_reset_warnings(); /* first, reload config variables, in case they've changed */ if (options->ReloadTorrcOnSIGHUP) { /* no need to provide argc/v, they've been cached in init_from_config */ if (options_init_from_torrc(0, NULL) < 0) { log_err(LD_CONFIG,"Reading config failed--see warnings above. " "For usage, try -h."); return -1; } options = get_options(); /* they have changed now */ } else { char *msg = NULL; log_notice(LD_GENERAL, "Not reloading config file: the controller told " "us not to."); /* Make stuff get rescanned, reloaded, etc. */ if (set_options((or_options_t*)options, &msg) < 0) { if (!msg) msg = tor_strdup("Unknown error"); log_warn(LD_GENERAL, "Unable to re-set previous options: %s", msg); tor_free(msg); } } if (authdir_mode_handles_descs(options, -1)) { /* reload the approved-routers file */ if (dirserv_load_fingerprint_file() < 0) { /* warnings are logged from dirserv_load_fingerprint_file() directly */ log_info(LD_GENERAL, "Error reloading fingerprints. " "Continuing with old list."); } } /* Rotate away from the old dirty circuits. This has to be done * after we've read the new options, but before we start using * circuits for directory fetches. */ circuit_mark_all_dirty_circs_as_unusable(); /* retry appropriate downloads */ router_reset_status_download_failures(); router_reset_descriptor_download_failures(); if (!options->DisableNetwork) update_networkstatus_downloads(time(NULL)); /* We'll retry routerstatus downloads in about 10 seconds; no need to * force a retry there. */ if (server_mode(options)) { /* Restart cpuworker and dnsworker processes, so they get up-to-date * configuration options. */ cpuworkers_rotate(); dns_reset(); } return 0; } /** Tor main loop. */ int do_main_loop(void) { int loop_result; time_t now; /* initialize dns resolve map, spawn workers if needed */ if (dns_init() < 0) { if (get_options()->ServerDNSAllowBrokenConfig) log_warn(LD_GENERAL, "Couldn't set up any working nameservers. " "Network not up yet? Will try again soon."); else { log_err(LD_GENERAL,"Error initializing dns subsystem; exiting. To " "retry instead, set the ServerDNSAllowBrokenResolvConf option."); } } #ifdef USE_BUFFEREVENTS log_warn(LD_GENERAL, "Tor was compiled with the --enable-bufferevents " "option. This is still experimental, and might cause strange " "bugs. If you want a more stable Tor, be sure to build without " "--enable-bufferevents."); #endif handle_signals(1); /* load the private keys, if we're supposed to have them, and set up the * TLS context. */ if (! client_identity_key_is_set()) { if (init_keys() < 0) { log_err(LD_BUG,"Error initializing keys; exiting"); return -1; } } #ifdef ENABLE_MEMPOOLS /* Set up the packed_cell_t memory pool. */ init_cell_pool(); #endif /* ENABLE_MEMPOOLS */ /* Set up our buckets */ connection_bucket_init(); #ifndef USE_BUFFEREVENTS stats_prev_global_read_bucket = global_read_bucket; stats_prev_global_write_bucket = global_write_bucket; #endif /* initialize the bootstrap status events to know we're starting up */ control_event_bootstrap(BOOTSTRAP_STATUS_STARTING, 0); if (trusted_dirs_reload_certs()) { log_warn(LD_DIR, "Couldn't load all cached v3 certificates. Starting anyway."); } if (router_reload_consensus_networkstatus()) { return -1; } /* load the routers file, or assign the defaults. */ if (router_reload_router_list()) { return -1; } /* load the networkstatuses. (This launches a download for new routers as * appropriate.) */ now = time(NULL); directory_info_has_arrived(now, 1); if (server_mode(get_options())) { /* launch cpuworkers. Need to do this *after* we've read the onion key. */ cpu_init(); } /* set up once-a-second callback. */ if (! second_timer) { struct timeval one_second; one_second.tv_sec = 1; one_second.tv_usec = 0; second_timer = periodic_timer_new(tor_libevent_get_base(), &one_second, second_elapsed_callback, NULL); tor_assert(second_timer); } #ifndef USE_BUFFEREVENTS if (!refill_timer) { struct timeval refill_interval; int msecs = get_options()->TokenBucketRefillInterval; refill_interval.tv_sec = msecs/1000; refill_interval.tv_usec = (msecs%1000)*1000; refill_timer = periodic_timer_new(tor_libevent_get_base(), &refill_interval, refill_callback, NULL); tor_assert(refill_timer); } #endif for (;;) { if (nt_service_is_stopping()) return 0; #ifndef _WIN32 /* Make it easier to tell whether libevent failure is our fault or not. */ errno = 0; #endif /* All active linked conns should get their read events activated. */ SMARTLIST_FOREACH(active_linked_connection_lst, connection_t *, conn, event_active(conn->read_event, EV_READ, 1)); called_loop_once = smartlist_len(active_linked_connection_lst) ? 1 : 0; update_approx_time(time(NULL)); /* poll until we have an event, or the second ends, or until we have * some active linked connections to trigger events for. */ loop_result = event_base_loop(tor_libevent_get_base(), called_loop_once ? EVLOOP_ONCE : 0); /* let catch() handle things like ^c, and otherwise don't worry about it */ if (loop_result < 0) { int e = tor_socket_errno(-1); /* let the program survive things like ^z */ if (e != EINTR && !ERRNO_IS_EINPROGRESS(e)) { log_err(LD_NET,"libevent call with %s failed: %s [%d]", tor_libevent_get_method(), tor_socket_strerror(e), e); return -1; #ifndef _WIN32 } else if (e == EINVAL) { log_warn(LD_NET, "EINVAL from libevent: should you upgrade libevent?"); if (got_libevent_error()) return -1; #endif } else { if (ERRNO_IS_EINPROGRESS(e)) log_warn(LD_BUG, "libevent call returned EINPROGRESS? Please report."); log_debug(LD_NET,"libevent call interrupted."); /* You can't trust the results of this poll(). Go back to the * top of the big for loop. */ continue; } } } } #ifndef _WIN32 /* Only called when we're willing to use signals */ /** Libevent callback: invoked when we get a signal. */ static void signal_callback(int fd, short events, void *arg) { uintptr_t sig = (uintptr_t)arg; (void)fd; (void)events; process_signal(sig); } #endif /** Do the work of acting on a signal received in sig */ void process_signal(uintptr_t sig) { switch (sig) { case SIGTERM: log_notice(LD_GENERAL,"Catching signal TERM, exiting cleanly."); tor_cleanup(); exit(0); break; case SIGINT: if (!server_mode(get_options())) { /* do it now */ log_notice(LD_GENERAL,"Interrupt: exiting cleanly."); tor_cleanup(); exit(0); } hibernate_begin_shutdown(); break; #ifdef SIGPIPE case SIGPIPE: log_debug(LD_GENERAL,"Caught SIGPIPE. Ignoring."); break; #endif case SIGUSR1: /* prefer to log it at INFO, but make sure we always see it */ dumpstats(get_min_log_level() 0) ; /* keep reaping until no more zombies */ break; #endif case SIGNEWNYM: { time_t now = time(NULL); if (time_of_last_signewnym + MAX_SIGNEWNYM_RATE > now) { signewnym_is_pending = 1; log_notice(LD_CONTROL, "Rate limiting NEWNYM request: delaying by %d second(s)", (int)(MAX_SIGNEWNYM_RATE+time_of_last_signewnym-now)); } else { signewnym_impl(now); } break; } case SIGCLEARDNSCACHE: addressmap_clear_transient(); control_event_signal(sig); break; } } /** Returns Tor's uptime. */ MOCK_IMPL(long, get_uptime,(void)) { return stats_n_seconds_working; } extern uint64_t rephist_total_alloc; extern uint32_t rephist_total_num; /** * Write current memory usage information to the log. */ static void dumpmemusage(int severity) { connection_dump_buffer_mem_stats(severity); tor_log(severity, LD_GENERAL, "In rephist: "U64_FORMAT" used by %d Tors.", U64_PRINTF_ARG(rephist_total_alloc), rephist_total_num); dump_routerlist_mem_usage(severity); dump_cell_pool_usage(severity); dump_dns_mem_usage(severity); buf_dump_freelist_sizes(severity); tor_log_mallinfo(severity); } /** Write all statistics to the log, with log level severity. Called * in response to a SIGUSR1. */ static void dumpstats(int severity) { time_t now = time(NULL); time_t elapsed; size_t rbuf_cap, wbuf_cap, rbuf_len, wbuf_len; tor_log(severity, LD_GENERAL, "Dumping stats:"); SMARTLIST_FOREACH_BEGIN(connection_array, connection_t *, conn) { int i = conn_sl_idx; tor_log(severity, LD_GENERAL, "Conn %d (socket %d) type %d (%s), state %d (%s), created %d secs ago", i, (int)conn->s, conn->type, conn_type_to_string(conn->type), conn->state, conn_state_to_string(conn->type, conn->state), (int)(now - conn->timestamp_created)); if (!connection_is_listener(conn)) { tor_log(severity,LD_GENERAL, "Conn %d is to %s:%d.", i, safe_str_client(conn->address), conn->port); tor_log(severity,LD_GENERAL, "Conn %d: %d bytes waiting on inbuf (len %d, last read %d secs ago)", i, (int)connection_get_inbuf_len(conn), (int)buf_allocation(conn->inbuf), (int)(now - conn->timestamp_lastread)); tor_log(severity,LD_GENERAL, "Conn %d: %d bytes waiting on outbuf " "(len %d, last written %d secs ago)",i, (int)connection_get_outbuf_len(conn), (int)buf_allocation(conn->outbuf), (int)(now - conn->timestamp_lastwritten)); if (conn->type == CONN_TYPE_OR) { or_connection_t *or_conn = TO_OR_CONN(conn); if (or_conn->tls) { tor_tls_get_buffer_sizes(or_conn->tls, &rbuf_cap, &rbuf_len, &wbuf_cap, &wbuf_len); tor_log(severity, LD_GENERAL, "Conn %d: %d/%d bytes used on OpenSSL read buffer; " "%d/%d bytes used on write buffer.", i, (int)rbuf_len, (int)rbuf_cap, (int)wbuf_len, (int)wbuf_cap); } } } circuit_dump_by_conn(conn, severity); /* dump info about all the circuits * using this conn */ } SMARTLIST_FOREACH_END(conn); channel_dumpstats(severity); channel_listener_dumpstats(severity); tor_log(severity, LD_NET, "Cells processed: "U64_FORMAT" padding\n" " "U64_FORMAT" create\n" " "U64_FORMAT" created\n" " "U64_FORMAT" relay\n" " ("U64_FORMAT" relayed)\n" " ("U64_FORMAT" delivered)\n" " "U64_FORMAT" destroy", U64_PRINTF_ARG(stats_n_padding_cells_processed), U64_PRINTF_ARG(stats_n_create_cells_processed), U64_PRINTF_ARG(stats_n_created_cells_processed), U64_PRINTF_ARG(stats_n_relay_cells_processed), U64_PRINTF_ARG(stats_n_relay_cells_relayed), U64_PRINTF_ARG(stats_n_relay_cells_delivered), U64_PRINTF_ARG(stats_n_destroy_cells_processed)); if (stats_n_data_cells_packaged) tor_log(severity,LD_NET,"Average packaged cell fullness: %2.3f%%", 100*(U64_TO_DBL(stats_n_data_bytes_packaged) / U64_TO_DBL(stats_n_data_cells_packaged*RELAY_PAYLOAD_SIZE)) ); if (stats_n_data_cells_received) tor_log(severity,LD_NET,"Average delivered cell fullness: %2.3f%%", 100*(U64_TO_DBL(stats_n_data_bytes_received) / U64_TO_DBL(stats_n_data_cells_received*RELAY_PAYLOAD_SIZE)) ); cpuworker_log_onionskin_overhead(severity, ONION_HANDSHAKE_TYPE_TAP, "TAP"); cpuworker_log_onionskin_overhead(severity, ONION_HANDSHAKE_TYPE_NTOR,"ntor"); if (now - time_of_process_start >= 0) elapsed = now - time_of_process_start; else elapsed = 0; if (elapsed) { tor_log(severity, LD_NET, "Average bandwidth: "U64_FORMAT"/%d = %d bytes/sec reading", U64_PRINTF_ARG(stats_n_bytes_read), (int)elapsed, (int) (stats_n_bytes_read/elapsed)); tor_log(severity, LD_NET, "Average bandwidth: "U64_FORMAT"/%d = %d bytes/sec writing", U64_PRINTF_ARG(stats_n_bytes_written), (int)elapsed, (int) (stats_n_bytes_written/elapsed)); } tor_log(severity, LD_NET, "--------------- Dumping memory information:"); dumpmemusage(severity); rep_hist_dump_stats(now,severity); rend_service_dump_stats(severity); dump_pk_ops(severity); dump_distinct_digest_count(severity); } /** Called by exit() as we shut down the process. */ static void exit_function(void) { /* NOTE: If we ever daemonize, this gets called immediately. That's * okay for now, because we only use this on Windows. */ #ifdef _WIN32 WSACleanup(); #endif } /** Set up the signal handlers for either parent or child. */ void handle_signals(int is_parent) { #ifndef _WIN32 /* do signal stuff only on Unix */ int i; static const int signals[] = { SIGINT, /* do a controlled slow shutdown */ SIGTERM, /* to terminate now */ SIGPIPE, /* otherwise SIGPIPE kills us */ SIGUSR1, /* dump stats */ SIGUSR2, /* go to loglevel debug */ SIGHUP, /* to reload config, retry conns, etc */ #ifdef SIGXFSZ SIGXFSZ, /* handle file-too-big resource exhaustion */ #endif SIGCHLD, /* handle dns/cpu workers that exit */ -1 }; static struct event *signal_events[16]; /* bigger than it has to be. */ if (is_parent) { for (i = 0; signals[i] >= 0; ++i) { signal_events[i] = tor_evsignal_new( tor_libevent_get_base(), signals[i], signal_callback, (void*)(uintptr_t)signals[i]); if (event_add(signal_events[i], NULL)) log_warn(LD_BUG, "Error from libevent when adding event for signal %d", signals[i]); } } else { struct sigaction action; action.sa_flags = 0; sigemptyset(&action.sa_mask); action.sa_handler = SIG_IGN; sigaction(SIGINT, &action, NULL); sigaction(SIGTERM, &action, NULL); sigaction(SIGPIPE, &action, NULL); sigaction(SIGUSR1, &action, NULL); sigaction(SIGUSR2, &action, NULL); sigaction(SIGHUP, &action, NULL); #ifdef SIGXFSZ sigaction(SIGXFSZ, &action, NULL); #endif } #else /* MS windows */ (void)is_parent; #endif /* signal stuff */ } /** Main entry point for the Tor command-line client. */ int tor_init(int argc, char *argv[]) { char progname[256]; int quiet = 0; time_of_process_start = time(NULL); init_connection_lists(); /* Have the log set up with our application name. */ tor_snprintf(progname, sizeof(progname), "Tor %s", get_version()); log_set_application_name(progname); /* Set up the crypto nice and early */ if (crypto_early_init() < 0) { log_err(LD_GENERAL, "Unable to initialize the crypto subsystem!"); return 1; } /* Initialize the history structures. */ rep_hist_init(); /* Initialize the service cache. */ rend_cache_init(); addressmap_init(); /* Init the client dns cache. Do it always, since it's * cheap. */ { /* We search for the "quiet" option first, since it decides whether we * will log anything at all to the command line. */ config_line_t *opts = NULL, *cmdline_opts = NULL; const config_line_t *cl; (void) config_parse_commandline(argc, argv, 1, &opts, &cmdline_opts); for (cl = cmdline_opts; cl; cl = cl->next) { if (!strcmp(cl->key, "--hush")) quiet = 1; if (!strcmp(cl->key, "--quiet") || !strcmp(cl->key, "--dump-config")) quiet = 2; /* --version, --digests, and --help imply --hush */ if (!strcmp(cl->key, "--version") || !strcmp(cl->key, "--digests") || !strcmp(cl->key, "--list-torrc-options") || !strcmp(cl->key, "--library-versions") || !strcmp(cl->key, "-h") || !strcmp(cl->key, "--help")) { if (quiet < 1) quiet = 1; } } config_free_lines(opts); config_free_lines(cmdline_opts); } /* give it somewhere to log to initially */ switch (quiet) { case 2: /* no initial logging */ break; case 1: add_temp_log(LOG_WARN); break; default: add_temp_log(LOG_NOTICE); } quiet_level = quiet; { const char *version = get_version(); const char *bev_str = #ifdef USE_BUFFEREVENTS "(with bufferevents) "; #else ""; #endif log_notice(LD_GENERAL, "Tor v%s %srunning on %s with Libevent %s, " "OpenSSL %s and Zlib %s.", version, bev_str, get_uname(), tor_libevent_get_version_str(), crypto_openssl_get_version_str(), tor_zlib_get_version_str()); log_notice(LD_GENERAL, "Tor can't help you if you use it wrong! " "Learn how to be safe at " "https://www.torproject.org/download/download#warning"); if (strstr(version, "alpha") || strstr(version, "beta")) log_notice(LD_GENERAL, "This version is not a stable Tor release. " "Expect more bugs than usual."); } #ifdef NON_ANONYMOUS_MODE_ENABLED log_warn(LD_GENERAL, "This copy of Tor was compiled to run in a " "non-anonymous mode. It will provide NO ANONYMITY."); #endif if (network_init()<0) { log_err(LD_BUG,"Error initializing network; exiting."); return -1; } atexit(exit_function); if (options_init_from_torrc(argc,argv) < 0) { log_err(LD_CONFIG,"Reading config failed--see warnings above."); return -1; } #ifndef _WIN32 if (geteuid()==0) log_warn(LD_GENERAL,"You are running Tor as root. You don't need to, " "and you probably shouldn't."); #endif if (crypto_global_init(get_options()->HardwareAccel, get_options()->AccelName, get_options()->AccelDir)) { log_err(LD_BUG, "Unable to initialize OpenSSL. Exiting."); return -1; } stream_choice_seed_weak_rng(); if (tor_init_libevent_rng() < 0) { log_warn(LD_NET, "Problem initializing libevent RNG."); } return 0; } /** A lockfile structure, used to prevent two Tors from messing with the * data directory at once. If this variable is non-NULL, we're holding * the lockfile. */ static tor_lockfile_t *lockfile = NULL; /** Try to grab the lock file described in options, if we do not * already have it. If err_if_locked is true, warn if somebody else is * holding the lock, and exit if we can't get it after waiting. Otherwise, * return -1 if we can't get the lockfile. Return 0 on success. */ int try_locking(const or_options_t *options, int err_if_locked) { if (lockfile) return 0; else { char *fname = options_get_datadir_fname2_suffix(options, "lock",NULL,NULL); int already_locked = 0; tor_lockfile_t *lf = tor_lockfile_lock(fname, 0, &already_locked); tor_free(fname); if (!lf) { if (err_if_locked && already_locked) { int r; log_warn(LD_GENERAL, "It looks like another Tor process is running " "with the same data directory. Waiting 5 seconds to see " "if it goes away."); #ifndef _WIN32 sleep(5); #else Sleep(5000); #endif r = try_locking(options, 0); if (r<0) { log_err(LD_GENERAL, "No, it's still there. Exiting."); exit(0); } return r; } return -1; } lockfile = lf; return 0; } } /** Return true iff we've successfully acquired the lock file. */ int have_lockfile(void) { return lockfile != NULL; } /** If we have successfully acquired the lock file, release it. */ void release_lockfile(void) { if (lockfile) { tor_lockfile_unlock(lockfile); lockfile = NULL; } } /** Free all memory that we might have allocated somewhere. * If postfork, we are a worker process and we want to free * only the parts of memory that we won't touch. If !postfork, * Tor is shutting down and we should free everything. * * Helps us find the real leaks with dmalloc and the like. Also valgrind * should then report 0 reachable in its leak report (in an ideal world -- * in practice libevent, SSL, libc etc never quite free everything). */ void tor_free_all(int postfork) { if (!postfork) { evdns_shutdown(1); } geoip_free_all(); dirvote_free_all(); routerlist_free_all(); networkstatus_free_all(); addressmap_free_all(); dirserv_free_all(); rend_service_free_all(); rend_cache_free_all(); rend_service_authorization_free_all(); rep_hist_free_all(); dns_free_all(); clear_pending_onions(); circuit_free_all(); entry_guards_free_all(); pt_free_all(); channel_tls_free_all(); channel_free_all(); connection_free_all(); buf_shrink_freelists(1); memarea_clear_freelist(); nodelist_free_all(); microdesc_free_all(); ext_orport_free_all(); control_free_all(); if (!postfork) { config_free_all(); or_state_free_all(); router_free_all(); policies_free_all(); } #ifdef ENABLE_MEMPOOLS free_cell_pool(); #endif /* ENABLE_MEMPOOLS */ if (!postfork) { tor_tls_free_all(); #ifndef _WIN32 tor_getpwnam(NULL); #endif } /* stuff in main.c */ smartlist_free(connection_array); smartlist_free(closeable_connection_lst); smartlist_free(active_linked_connection_lst); periodic_timer_free(second_timer); #ifndef USE_BUFFEREVENTS periodic_timer_free(refill_timer); #endif if (!postfork) { release_lockfile(); } /* Stuff in util.c and address.c*/ if (!postfork) { escaped(NULL); esc_router_info(NULL); logs_free_all(); /* free log strings. do this last so logs keep working. */ } } /** Do whatever cleanup is necessary before shutting Tor down. */ void tor_cleanup(void) { const or_options_t *options = get_options(); if (options->command == CMD_RUN_TOR) { time_t now = time(NULL); /* Remove our pid file. We don't care if there was an error when we * unlink, nothing we could do about it anyways. */ if (options->PidFile) { if (unlink(options->PidFile) != 0) { log_warn(LD_FS, "Couldn't unlink pid file %s: %s", options->PidFile, strerror(errno)); } } if (options->ControlPortWriteToFile) { if (unlink(options->ControlPortWriteToFile) != 0) { log_warn(LD_FS, "Couldn't unlink control port file %s: %s", options->ControlPortWriteToFile, strerror(errno)); } } if (accounting_is_enabled(options)) accounting_record_bandwidth_usage(now, get_or_state()); or_state_mark_dirty(get_or_state(), 0); /* force an immediate save. */ or_state_save(now); if (authdir_mode_tests_reachability(options)) rep_hist_record_mtbf_data(now, 0); } #ifdef USE_DMALLOC dmalloc_log_stats(); #endif tor_free_all(0); /* We could move tor_free_all back into the ifdef below later, if it makes shutdown unacceptably slow. But for now, leave it here: it's helped us catch bugs in the past. */ crypto_global_cleanup(); #ifdef USE_DMALLOC dmalloc_log_unfreed(); dmalloc_shutdown(); #endif } /** Read/create keys as needed, and echo our fingerprint to stdout. */ static int do_list_fingerprint(void) { char buf[FINGERPRINT_LEN+1]; crypto_pk_t *k; const char *nickname = get_options()->Nickname; if (!server_mode(get_options())) { log_err(LD_GENERAL, "Clients don't have long-term identity keys. Exiting."); return -1; } tor_assert(nickname); if (init_keys() < 0) { log_err(LD_BUG,"Error initializing keys; can't display fingerprint"); return -1; } if (!(k = get_server_identity_key())) { log_err(LD_GENERAL,"Error: missing identity key."); return -1; } if (crypto_pk_get_fingerprint(k, buf, 1)<0) { log_err(LD_BUG, "Error computing fingerprint"); return -1; } printf("%s %s\n", nickname, buf); return 0; } /** Entry point for password hashing: take the desired password from * the command line, and print its salted hash to stdout. **/ static void do_hash_password(void) { char output[256]; char key[S2K_SPECIFIER_LEN+DIGEST_LEN]; crypto_rand(key, S2K_SPECIFIER_LEN-1); key[S2K_SPECIFIER_LEN-1] = (uint8_t)96; /* Hash 64 K of data. */ secret_to_key(key+S2K_SPECIFIER_LEN, DIGEST_LEN, get_options()->command_arg, strlen(get_options()->command_arg), key); base16_encode(output, sizeof(output), key, sizeof(key)); printf("16:%s\n",output); } /** Entry point for configuration dumping: write the configuration to * stdout. */ static int do_dump_config(void) { const or_options_t *options = get_options(); const char *arg = options->command_arg; int how; char *opts; if (!strcmp(arg, "short")) { how = OPTIONS_DUMP_MINIMAL; } else if (!strcmp(arg, "non-builtin")) { how = OPTIONS_DUMP_DEFAULTS; } else if (!strcmp(arg, "full")) { how = OPTIONS_DUMP_ALL; } else { printf("%s is not a recognized argument to --dump-config. " "Please select 'short', 'non-builtin', or 'full'", arg); return -1; } opts = options_dump(options, how); printf("%s", opts); tor_free(opts); return 0; } #if defined (WINCE) int find_flashcard_path(PWCHAR path, size_t size) { WIN32_FIND_DATA d = {0}; HANDLE h = NULL; if (!path) return -1; h = FindFirstFlashCard(&d); if (h == INVALID_HANDLE_VALUE) return -1; if (wcslen(d.cFileName) == 0) { FindClose(h); return -1; } wcsncpy(path,d.cFileName,size); FindClose(h); return 0; } #endif static void init_addrinfo(void) { char hname[256]; // host name to sandbox gethostname(hname, sizeof(hname)); sandbox_add_addrinfo(hname); } static sandbox_cfg_t* sandbox_init_filter(void) { const or_options_t *options = get_options(); sandbox_cfg_t *cfg = sandbox_cfg_new(); int i; sandbox_cfg_allow_openat_filename(&cfg, get_datadir_fname("cached-status")); sandbox_cfg_allow_open_filename_array(&cfg, get_datadir_fname("cached-certs"), get_datadir_fname("cached-certs.tmp"), get_datadir_fname("cached-consensus"), get_datadir_fname("cached-consensus.tmp"), get_datadir_fname("unverified-consensus"), get_datadir_fname("unverified-consensus.tmp"), get_datadir_fname("unverified-microdesc-consensus"), get_datadir_fname("unverified-microdesc-consensus.tmp"), get_datadir_fname("cached-microdesc-consensus"), get_datadir_fname("cached-microdesc-consensus.tmp"), get_datadir_fname("cached-microdescs"), get_datadir_fname("cached-microdescs.tmp"), get_datadir_fname("cached-microdescs.new"), get_datadir_fname("cached-microdescs.new.tmp"), get_datadir_fname("cached-descriptors"), get_datadir_fname("cached-descriptors.new"), get_datadir_fname("cached-descriptors.tmp"), get_datadir_fname("cached-descriptors.new.tmp"), get_datadir_fname("cached-descriptors.tmp.tmp"), get_datadir_fname("cached-extrainfo"), get_datadir_fname("cached-extrainfo.new"), get_datadir_fname("cached-extrainfo.tmp"), get_datadir_fname("cached-extrainfo.new.tmp"), get_datadir_fname("cached-extrainfo.tmp.tmp"), get_datadir_fname("state.tmp"), get_datadir_fname("unparseable-desc.tmp"), get_datadir_fname("unparseable-desc"), get_datadir_fname("v3-status-votes"), get_datadir_fname("v3-status-votes.tmp"), tor_strdup("/dev/srandom"), tor_strdup("/dev/urandom"), tor_strdup("/dev/random"), tor_strdup("/etc/hosts"), tor_strdup("/proc/meminfo"), NULL, 0 ); if (options->ServerDNSResolvConfFile) sandbox_cfg_allow_open_filename(&cfg, tor_strdup(options->ServerDNSResolvConfFile)); else sandbox_cfg_allow_open_filename(&cfg, tor_strdup("/etc/resolv.conf")); for (i = 0; i < 2; ++i) { if (get_torrc_fname(i)) { sandbox_cfg_allow_open_filename(&cfg, tor_strdup(get_torrc_fname(i))); } } #define RENAME_SUFFIX(name, suffix) \ sandbox_cfg_allow_rename(&cfg, \ get_datadir_fname(name suffix), \ get_datadir_fname(name)) #define RENAME_SUFFIX2(prefix, name, suffix) \ sandbox_cfg_allow_rename(&cfg, \ get_datadir_fname2(prefix, name suffix), \ get_datadir_fname2(prefix, name)) RENAME_SUFFIX("cached-certs", ".tmp"); RENAME_SUFFIX("cached-consensus", ".tmp"); RENAME_SUFFIX("unverified-consensus", ".tmp"); RENAME_SUFFIX("unverified-microdesc-consensus", ".tmp"); RENAME_SUFFIX("cached-microdesc-consensus", ".tmp"); RENAME_SUFFIX("cached-microdescs", ".tmp"); RENAME_SUFFIX("cached-microdescs", ".new"); RENAME_SUFFIX("cached-microdescs.new", ".tmp"); RENAME_SUFFIX("cached-descriptors", ".tmp"); RENAME_SUFFIX("cached-descriptors", ".new"); RENAME_SUFFIX("cached-descriptors.new", ".tmp"); RENAME_SUFFIX("cached-extrainfo", ".tmp"); RENAME_SUFFIX("cached-extrainfo", ".new"); RENAME_SUFFIX("cached-extrainfo.new", ".tmp"); RENAME_SUFFIX("state", ".tmp"); RENAME_SUFFIX("unparseable-desc", ".tmp"); RENAME_SUFFIX("v3-status-votes", ".tmp"); sandbox_cfg_allow_stat_filename_array(&cfg, get_datadir_fname(NULL), get_datadir_fname("lock"), get_datadir_fname("state"), get_datadir_fname("router-stability"), get_datadir_fname("cached-extrainfo.new"), NULL, 0 ); { smartlist_t *files = smartlist_new(); tor_log_get_logfile_names(files); SMARTLIST_FOREACH(files, char *, file_name, { /* steals reference */ sandbox_cfg_allow_open_filename(&cfg, file_name); }); smartlist_free(files); } { smartlist_t *files = smartlist_new(); smartlist_t *dirs = smartlist_new(); rend_services_add_filenames_to_lists(files, dirs); SMARTLIST_FOREACH(files, char *, file_name, { char *tmp_name = NULL; tor_asprintf(&tmp_name, "%s.tmp", file_name); sandbox_cfg_allow_rename(&cfg, tor_strdup(tmp_name), tor_strdup(file_name)); /* steals references */ sandbox_cfg_allow_open_filename_array(&cfg, file_name, tmp_name, NULL); }); SMARTLIST_FOREACH(dirs, char *, dir, { /* steals reference */ sandbox_cfg_allow_stat_filename(&cfg, dir); }); smartlist_free(files); smartlist_free(dirs); } { char *fname; if ((fname = get_controller_cookie_file_name())) { sandbox_cfg_allow_open_filename(&cfg, fname); } if ((fname = get_ext_or_auth_cookie_file_name())) { sandbox_cfg_allow_open_filename(&cfg, fname); } } if (options->DirPortFrontPage) { sandbox_cfg_allow_open_filename(&cfg, tor_strdup(options->DirPortFrontPage)); } // orport if (server_mode(get_options())) { sandbox_cfg_allow_open_filename_array(&cfg, get_datadir_fname2("keys", "secret_id_key"), get_datadir_fname2("keys", "secret_onion_key"), get_datadir_fname2("keys", "secret_onion_key_ntor"), get_datadir_fname2("keys", "secret_onion_key_ntor.tmp"), get_datadir_fname2("keys", "secret_id_key.old"), get_datadir_fname2("keys", "secret_onion_key.old"), get_datadir_fname2("keys", "secret_onion_key_ntor.old"), get_datadir_fname2("keys", "secret_onion_key.tmp"), get_datadir_fname2("keys", "secret_id_key.tmp"), get_datadir_fname2("stats", "bridge-stats"), get_datadir_fname2("stats", "bridge-stats.tmp"), get_datadir_fname2("stats", "dirreq-stats"), get_datadir_fname2("stats", "dirreq-stats.tmp"), get_datadir_fname2("stats", "entry-stats"), get_datadir_fname2("stats", "entry-stats.tmp"), get_datadir_fname2("stats", "exit-stats"), get_datadir_fname2("stats", "exit-stats.tmp"), get_datadir_fname2("stats", "buffer-stats"), get_datadir_fname2("stats", "buffer-stats.tmp"), get_datadir_fname2("stats", "conn-stats"), get_datadir_fname2("stats", "conn-stats.tmp"), get_datadir_fname("approved-routers"), get_datadir_fname("fingerprint"), get_datadir_fname("fingerprint.tmp"), get_datadir_fname("hashed-fingerprint"), get_datadir_fname("hashed-fingerprint.tmp"), get_datadir_fname("router-stability"), get_datadir_fname("router-stability.tmp"), tor_strdup("/etc/resolv.conf"), NULL, 0 ); RENAME_SUFFIX("fingerprint", ".tmp"); RENAME_SUFFIX2("keys", "secret_onion_key_ntor", ".tmp"); RENAME_SUFFIX2("keys", "secret_id_key", ".tmp"); RENAME_SUFFIX2("keys", "secret_id_key.old", ".tmp"); RENAME_SUFFIX2("keys", "secret_onion_key", ".tmp"); RENAME_SUFFIX2("keys", "secret_onion_key.old", ".tmp"); RENAME_SUFFIX2("stats", "bridge-stats", ".tmp"); RENAME_SUFFIX2("stats", "dirreq-stats", ".tmp"); RENAME_SUFFIX2("stats", "entry-stats", ".tmp"); RENAME_SUFFIX2("stats", "exit-stats", ".tmp"); RENAME_SUFFIX2("stats", "buffer-stats", ".tmp"); RENAME_SUFFIX2("stats", "conn-stats", ".tmp"); RENAME_SUFFIX("hashed-fingerprint", ".tmp"); RENAME_SUFFIX("router-stability", ".tmp"); sandbox_cfg_allow_rename(&cfg, get_datadir_fname2("keys", "secret_onion_key"), get_datadir_fname2("keys", "secret_onion_key.old")); sandbox_cfg_allow_rename(&cfg, get_datadir_fname2("keys", "secret_onion_key_ntor"), get_datadir_fname2("keys", "secret_onion_key_ntor.old")); sandbox_cfg_allow_stat_filename_array(&cfg, get_datadir_fname("keys"), get_datadir_fname2("stats", "dirreq-stats"), NULL, 0 ); } init_addrinfo(); return cfg; } /** Main entry point for the Tor process. Called from main(). */ /* This function is distinct from main() only so we can link main.c into * the unittest binary without conflicting with the unittests' main. */ int tor_main(int argc, char *argv[]) { int result = 0; #if defined (WINCE) WCHAR path [MAX_PATH] = {0}; WCHAR fullpath [MAX_PATH] = {0}; PWCHAR p = NULL; FILE* redir = NULL; FILE* redirdbg = NULL; // this is to facilitate debugging by opening // a file on a folder shared by the wm emulator. // if no flashcard (real or emulated) is present, // log files will be written in the root folder if (find_flashcard_path(path,MAX_PATH) == -1) { redir = _wfreopen( L"\\stdout.log", L"w", stdout ); redirdbg = _wfreopen( L"\\stderr.log", L"w", stderr ); } else { swprintf(fullpath,L"\\%s\\tor",path); CreateDirectory(fullpath,NULL); swprintf(fullpath,L"\\%s\\tor\\stdout.log",path); redir = _wfreopen( fullpath, L"w", stdout ); swprintf(fullpath,L"\\%s\\tor\\stderr.log",path); redirdbg = _wfreopen( fullpath, L"w", stderr ); } #endif #ifdef _WIN32 /* Call SetProcessDEPPolicy to permanently enable DEP. The function will not resolve on earlier versions of Windows, and failure is not dangerous. */ HMODULE hMod = GetModuleHandleA("Kernel32.dll"); if (hMod) { typedef BOOL (WINAPI *PSETDEP)(DWORD); PSETDEP setdeppolicy = (PSETDEP)GetProcAddress(hMod, "SetProcessDEPPolicy"); if (setdeppolicy) setdeppolicy(1); /* PROCESS_DEP_ENABLE */ } #endif configure_backtrace_handler(get_version()); update_approx_time(time(NULL)); tor_threads_init(); init_logging(); #ifdef USE_DMALLOC { /* Instruct OpenSSL to use our internal wrappers for malloc, realloc and free. */ int r = CRYPTO_set_mem_ex_functions(tor_malloc_, tor_realloc_, tor_free_); tor_assert(r); } #endif #ifdef NT_SERVICE { int done = 0; result = nt_service_parse_options(argc, argv, &done); if (done) return result; } #endif if (tor_init(argc, argv)<0) return -1; if (get_options()->Sandbox && get_options()->command == CMD_RUN_TOR) { sandbox_cfg_t* cfg = sandbox_init_filter(); if (sandbox_init(cfg)) { log_err(LD_BUG,"Failed to create syscall sandbox filter"); return -1; } // registering libevent rng #ifdef HAVE_EVUTIL_SECURE_RNG_SET_URANDOM_DEVICE_FILE evutil_secure_rng_set_urandom_device_file( (char*) sandbox_intern_string("/dev/urandom")); #endif } switch (get_options()->command) { case CMD_RUN_TOR: #ifdef NT_SERVICE nt_service_set_state(SERVICE_RUNNING); #endif result = do_main_loop(); break; case CMD_LIST_FINGERPRINT: result = do_list_fingerprint(); break; case CMD_HASH_PASSWORD: do_hash_password(); result = 0; break; case CMD_VERIFY_CONFIG: printf("Configuration was valid\n"); result = 0; break; case CMD_DUMP_CONFIG: result = do_dump_config(); break; case CMD_RUN_UNITTESTS: /* only set by test.c */ default: log_warn(LD_BUG,"Illegal command number %d: internal error.", get_options()->command); result = -1; } tor_cleanup(); return result; }