commit 56a3cef4d73922a687fa4256938b5c459aada42c
Merge: 698629f5a b5731cdf2
Author: Nick Mathewson <nickm(a)torproject.org>
Date: Tue Oct 16 17:33:58 2018 -0400
Merge branch 'bug27849_redux'
changes/ticket27849 | 5 +++++
src/core/mainloop/mainloop.c | 7 ++++++-
2 files changed, 11 insertions(+), 1 deletion(-)
diff --cc src/core/mainloop/mainloop.c
index 6c305c2b4,000000000..0f3fbbcce
mode 100644,000000..100644
--- a/src/core/mainloop/mainloop.c
+++ b/src/core/mainloop/mainloop.c
@@@ -1,2929 -1,0 +1,2934 @@@
+/* Copyright (c) 2001 Matej Pfajfar.
+ * Copyright (c) 2001-2004, Roger Dingledine.
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2018, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/**
+ * \file mainloop.c
+ * \brief Toplevel module. Handles signals, multiplexes between
+ * connections, implements main loop, and drives scheduled events.
+ *
+ * For the main loop itself; see run_main_loop_once(). It invokes the rest of
+ * Tor mostly through Libevent callbacks. Libevent callbacks can happen when
+ * a timer elapses, a signal is received, a socket is ready to read or write,
+ * or an event is manually activated.
+ *
+ * Most events in Tor are driven from these callbacks:
+ * <ul>
+ * <li>conn_read_callback() and conn_write_callback() here, which are
+ * invoked when a socket is ready to read or write respectively.
+ * <li>signal_callback(), which handles incoming signals.
+ * </ul>
+ * Other events are used for specific purposes, or for building more complex
+ * control structures. If you search for usage of tor_libevent_new(), you
+ * will find all the events that we construct in Tor.
+ *
+ * Tor has numerous housekeeping operations that need to happen
+ * regularly. They are handled in different ways:
+ * <ul>
+ * <li>The most frequent operations are handled after every read or write
+ * event, at the end of connection_handle_read() and
+ * connection_handle_write().
+ *
+ * <li>The next most frequent operations happen after each invocation of the
+ * main loop, in run_main_loop_once().
+ *
+ * <li>Once per second, we run all of the operations listed in
+ * second_elapsed_callback(), and in its child, run_scheduled_events().
+ *
+ * <li>Once-a-second operations are handled in second_elapsed_callback().
+ *
+ * <li>More infrequent operations take place based on the periodic event
+ * driver in periodic.c . These are stored in the periodic_events[]
+ * table.
+ * </ul>
+ *
+ **/
+
+#define MAINLOOP_PRIVATE
+#include "core/or/or.h"
+
+#include "app/config/config.h"
+#include "app/config/statefile.h"
+#include "app/main/ntmain.h"
+#include "core/mainloop/connection.h"
+#include "core/mainloop/cpuworker.h"
+#include "core/mainloop/mainloop.h"
+#include "core/mainloop/netstatus.h"
+#include "core/mainloop/periodic.h"
+#include "core/or/channel.h"
+#include "core/or/channelpadding.h"
+#include "core/or/channeltls.h"
+#include "core/or/circuitbuild.h"
+#include "core/or/circuitlist.h"
+#include "core/or/circuituse.h"
+#include "core/or/connection_edge.h"
+#include "core/or/connection_or.h"
+#include "core/or/dos.h"
+#include "core/or/status.h"
+#include "feature/client/addressmap.h"
+#include "feature/client/bridges.h"
+#include "feature/client/dnsserv.h"
+#include "feature/client/entrynodes.h"
+#include "feature/client/transports.h"
+#include "feature/control/control.h"
+#include "feature/dirauth/authmode.h"
+#include "feature/dirauth/reachability.h"
+#include "feature/dircache/consdiffmgr.h"
+#include "feature/dircache/dirserv.h"
+#include "feature/dircommon/directory.h"
+#include "feature/hibernate/hibernate.h"
+#include "feature/hs/hs_cache.h"
+#include "feature/hs/hs_client.h"
+#include "feature/hs/hs_service.h"
+#include "feature/nodelist/microdesc.h"
+#include "feature/nodelist/networkstatus.h"
+#include "feature/nodelist/nodelist.h"
+#include "feature/nodelist/routerlist.h"
+#include "feature/relay/dns.h"
+#include "feature/relay/routerkeys.h"
+#include "feature/relay/routermode.h"
+#include "feature/relay/selftest.h"
+#include "feature/rend/rendcache.h"
+#include "feature/rend/rendservice.h"
+#include "feature/stats/geoip_stats.h"
+#include "feature/stats/predict_ports.h"
+#include "feature/stats/rephist.h"
+#include "lib/container/buffers.h"
+#include "lib/crypt_ops/crypto_rand.h"
+#include "lib/err/backtrace.h"
+#include "lib/tls/buffers_tls.h"
+
+#include "lib/net/buffers_net.h"
+#include "lib/evloop/compat_libevent.h"
+
+#include <event2/event.h>
+
+#include "feature/dirauth/dirvote.h"
+#include "feature/dirauth/authmode.h"
+
+#include "core/or/cell_st.h"
+#include "core/or/entry_connection_st.h"
+#include "feature/nodelist/networkstatus_st.h"
+#include "core/or/or_connection_st.h"
+#include "app/config/or_state_st.h"
+#include "feature/nodelist/routerinfo_st.h"
+#include "core/or/socks_request_st.h"
+
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+#ifdef HAVE_SYSTEMD
+# if defined(__COVERITY__) && !defined(__INCLUDE_LEVEL__)
+/* Systemd's use of gcc's __INCLUDE_LEVEL__ extension macro appears to confuse
+ * Coverity. Here's a kludge to unconfuse it.
+ */
+# define __INCLUDE_LEVEL__ 2
+#endif /* defined(__COVERITY__) && !defined(__INCLUDE_LEVEL__) */
+#include <systemd/sd-daemon.h>
+#endif /* defined(HAVE_SYSTEMD) */
+
+/* Token bucket for all traffic. */
+token_bucket_rw_t global_bucket;
+
+/* Token bucket for relayed traffic. */
+token_bucket_rw_t global_relayed_bucket;
+
+/* 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? */
+static long stats_n_seconds_working = 0;
+/** How many times have we returned from the main loop successfully? */
+static uint64_t stats_n_main_loop_successes = 0;
+/** How many times have we received an error from the main loop? */
+static uint64_t stats_n_main_loop_errors = 0;
+/** How many times have we returned from the main loop with no events. */
+static uint64_t stats_n_main_loop_idle = 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;
+/** Mainloop event for the deferred signewnym call. */
+static mainloop_event_t *handle_deferred_signewnym_ev = NULL;
+/** 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
+ * <b>loop_once</b>. If so, there's no need to trigger a loopexit in order
+ * to handle linked connections. */
+static int called_loop_once = 0;
+/** Flag: if true, it's time to shut down, so the main loop should exit as
+ * soon as possible.
+ */
+static int main_loop_should_exit = 0;
+/** The return value that the main loop should yield when it exits, if
+ * main_loop_should_exit is true.
+ */
+static int main_loop_exit_value = 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.
+ */
+static int can_complete_circuits = 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)
+
+static int conn_close_if_marked(int i);
+static int run_main_loop_until_done(void);
+static void connection_start_reading_from_linked_conn(connection_t *conn);
+static int connection_should_read_from_linked_conn(connection_t *conn);
+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 void shutdown_did_not_work_callback(evutil_socket_t fd, short event,
+ void *arg) ATTR_NORETURN;
+
+/****************************************************************************
+ *
+ * This section contains accessors and other methods on the connection_array
+ * variables (which are global within this file and unavailable outside it).
+ *
+ ****************************************************************************/
+
+/** Return 1 if we have successfully built a circuit, and nothing has changed
+ * to make us think that maybe we can't.
+ */
+int
+have_completed_a_circuit(void)
+{
+ return can_complete_circuits;
+}
+
+/** Note that we have successfully built a circuit, so that reachability
+ * testing and introduction points and so on may be attempted. */
+void
+note_that_we_completed_a_circuit(void)
+{
+ can_complete_circuits = 1;
+}
+
+/** Note that something has happened (like a clock jump, or DisableNetwork) to
+ * make us think that maybe we can't complete circuits. */
+void
+note_that_we_maybe_cant_complete_circuits(void)
+{
+ can_complete_circuits = 0;
+}
+
+/** Add <b>conn</b> 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);
+
+ (void) is_connecting;
+
+ if (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 <b>conn</b> 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);
+ }
+ 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));
+
+ if (conn->type == CONN_TYPE_AP && conn->socket_family == AF_UNIX) {
+ log_info(LD_NET, "Closing SOCKS Unix socket connection");
+ }
+
+ 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 <b>conn</b> 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_clear_identity(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);
+}
+
+/**
+ * Callback: used to activate read events for all linked connections, so
+ * libevent knows to call their read callbacks. This callback run as a
+ * postloop event, so that the events _it_ activates don't happen until
+ * Libevent has a chance to check for other events.
+ */
+static void
+schedule_active_linked_connections_cb(mainloop_event_t *event, void *arg)
+{
+ (void)event;
+ (void)arg;
+
+ /* All active linked conns should get their read events activated,
+ * so that libevent knows to run their callbacks. */
+ SMARTLIST_FOREACH(active_linked_connection_lst, connection_t *, conn,
+ event_active(conn->read_event, EV_READ, 1));
+}
+
+/** Event that invokes schedule_active_linked_connections_cb. */
+static mainloop_event_t *schedule_active_linked_connections_event = NULL;
+
+/** Initialize the global connection list, closeable connection list,
+ * and active connection list. */
+void
+tor_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 <b>conn</b> 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);
+ mainloop_schedule_postloop_cleanup();
+}
+
+/** 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 <b>*array</b> to an array of all connections. <b>*array</b> must not
+ * be modified.
+ */
+MOCK_IMPL(smartlist_t *,
+get_connection_array, (void))
+{
+ if (!connection_array)
+ connection_array = smartlist_new();
+ return connection_array;
+}
+
+/**
+ * Return the amount of network traffic read, in bytes, over the life of this
+ * process.
+ */
+MOCK_IMPL(uint64_t,
+get_bytes_read,(void))
+{
+ return stats_n_bytes_read;
+}
+
+/**
+ * Return the amount of network traffic read, in bytes, over the life of this
+ * process.
+ */
+MOCK_IMPL(uint64_t,
+get_bytes_written,(void))
+{
+ return stats_n_bytes_written;
+}
+
+/**
+ * Increment the amount of network traffic read and written, over the life of
+ * this process.
+ */
+void
+stats_increment_bytes_read_and_written(uint64_t r, uint64_t w)
+{
+ stats_n_bytes_read += r;
+ stats_n_bytes_written += w;
+}
+
+/** Set the event mask on <b>conn</b> to <b>events</b>. (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 (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 <b>conn</b> is listening for read events. */
+int
+connection_is_reading(connection_t *conn)
+{
+ tor_assert(conn);
+
+ return conn->reading_from_linked_conn ||
+ (conn->read_event && event_pending(conn->read_event, EV_READ, NULL));
+}
+
+/** Reset our main loop counters. */
+void
+reset_main_loop_counters(void)
+{
+ stats_n_main_loop_successes = 0;
+ stats_n_main_loop_errors = 0;
+ stats_n_main_loop_idle = 0;
+}
+
+/** Increment the main loop success counter. */
+static void
+increment_main_loop_success_count(void)
+{
+ ++stats_n_main_loop_successes;
+}
+
+/** Get the main loop success counter. */
+uint64_t
+get_main_loop_success_count(void)
+{
+ return stats_n_main_loop_successes;
+}
+
+/** Increment the main loop error counter. */
+static void
+increment_main_loop_error_count(void)
+{
+ ++stats_n_main_loop_errors;
+}
+
+/** Get the main loop error counter. */
+uint64_t
+get_main_loop_error_count(void)
+{
+ return stats_n_main_loop_errors;
+}
+
+/** Increment the main loop idle counter. */
+static void
+increment_main_loop_idle_count(void)
+{
+ ++stats_n_main_loop_idle;
+}
+
+/** Get the main loop idle counter. */
+uint64_t
+get_main_loop_idle_count(void)
+{
+ return stats_n_main_loop_idle;
+}
+
+/** Check whether <b>conn</b> is correct in having (or not having) a
+ * read/write event (passed in <b>ev</b>). On success, return 0. On failure,
+ * log a warning and return -1. */
+static int
+connection_check_event(connection_t *conn, struct event *ev)
+{
+ int bad;
+
+ if (conn->type == CONN_TYPE_AP && TO_EDGE_CONN(conn)->is_dns_request) {
+ /* DNS requests which we launch through the dnsserv.c module do not have
+ * any underlying socket or any underlying linked connection, so they
+ * shouldn't have any attached events either.
+ */
+ bad = ev != NULL;
+ } else {
+ /* Everything else should have an underlying socket, or a linked
+ * connection (which is also tracked with a read_event/write_event pair).
+ */
+ bad = ev == NULL;
+ }
+
+ if (bad) {
+ log_warn(LD_BUG, "Event missing on connection %p [%s;%s]. "
+ "socket=%d. linked=%d. "
+ "is_dns_request=%d. Marked_for_close=%s:%d",
+ conn,
+ conn_type_to_string(conn->type),
+ conn_state_to_string(conn->type, conn->state),
+ (int)conn->s, (int)conn->linked,
+ (conn->type == CONN_TYPE_AP &&
+ TO_EDGE_CONN(conn)->is_dns_request),
+ conn->marked_for_close_file ? conn->marked_for_close_file : "-",
+ conn->marked_for_close
+ );
+ log_backtrace(LOG_WARN, LD_BUG, "Backtrace attached.");
+ return -1;
+ }
+ return 0;
+}
+
+/** Tell the main loop to stop notifying <b>conn</b> of any read events. */
+MOCK_IMPL(void,
+connection_stop_reading,(connection_t *conn))
+{
+ tor_assert(conn);
+
+ if (connection_check_event(conn, conn->read_event) < 0) {
+ return;
+ }
+
+ 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 <b>conn</b> of any read events. */
+MOCK_IMPL(void,
+connection_start_reading,(connection_t *conn))
+{
+ tor_assert(conn);
+
+ if (connection_check_event(conn, conn->read_event) < 0) {
+ return;
+ }
+
+ 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 <b>conn</b> is listening for write events. */
+int
+connection_is_writing(connection_t *conn)
+{
+ tor_assert(conn);
+
+ return conn->writing_to_linked_conn ||
+ (conn->write_event && event_pending(conn->write_event, EV_WRITE, NULL));
+}
+
+/** Tell the main loop to stop notifying <b>conn</b> of any write events. */
+MOCK_IMPL(void,
+connection_stop_writing,(connection_t *conn))
+{
+ tor_assert(conn);
+
+ if (connection_check_event(conn, conn->write_event) < 0) {
+ return;
+ }
+
+ 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 <b>conn</b> of any write events. */
+MOCK_IMPL(void,
+connection_start_writing,(connection_t *conn))
+{
+ tor_assert(conn);
+
+ if (connection_check_event(conn, conn->write_event) < 0) {
+ return;
+ }
+
+ 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 <b>conn</b> 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;
+}
+
+/** Event to run 'shutdown did not work callback'. */
+static struct event *shutdown_did_not_work_event = NULL;
+
+/** Failsafe measure that should never actually be necessary: If
+ * tor_shutdown_event_loop_and_exit() somehow doesn't successfully exit the
+ * event loop, then this callback will kill Tor with an assertion failure
+ * seconds later
+ */
+static void
+shutdown_did_not_work_callback(evutil_socket_t fd, short event, void *arg)
+{
+ // LCOV_EXCL_START
+ (void) fd;
+ (void) event;
+ (void) arg;
+ tor_assert_unreached();
+ // LCOV_EXCL_STOP
+}
+
+#ifdef ENABLE_RESTART_DEBUGGING
+static struct event *tor_shutdown_event_loop_for_restart_event = NULL;
+static void
+tor_shutdown_event_loop_for_restart_cb(
+ evutil_socket_t fd, short event, void *arg)
+{
+ (void)fd;
+ (void)event;
+ (void)arg;
+ tor_event_free(tor_shutdown_event_loop_for_restart_event);
+ tor_shutdown_event_loop_and_exit(0);
+}
+#endif
+
+/**
+ * After finishing the current callback (if any), shut down the main loop,
+ * clean up the process, and exit with <b>exitcode</b>.
+ */
+void
+tor_shutdown_event_loop_and_exit(int exitcode)
+{
+ if (main_loop_should_exit)
+ return; /* Ignore multiple calls to this function. */
+
+ main_loop_should_exit = 1;
+ main_loop_exit_value = exitcode;
+
+ /* Die with an assertion failure in ten seconds, if for some reason we don't
+ * exit normally. */
+ /* XXXX We should consider this code if it's never used. */
+ struct timeval ten_seconds = { 10, 0 };
+ shutdown_did_not_work_event = tor_evtimer_new(
+ tor_libevent_get_base(),
+ shutdown_did_not_work_callback, NULL);
+ event_add(shutdown_did_not_work_event, &ten_seconds);
+
+ /* Unlike exit_loop_after_delay(), exit_loop_after_callback
+ * prevents other callbacks from running. */
+ tor_libevent_exit_loop_after_callback(tor_libevent_get_base());
+}
+
+/** Return true iff tor_shutdown_event_loop_and_exit() has been called. */
+int
+tor_event_loop_shutdown_is_pending(void)
+{
+ return main_loop_should_exit;
+}
+
+/** Helper: Tell the main loop to begin reading bytes into <b>conn</b> 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);
+ mainloop_event_activate(schedule_active_linked_connections_event);
+ } else {
+ tor_assert(smartlist_contains(active_linked_connection_lst, conn));
+ }
+}
+
+/** Tell the main loop to stop reading bytes into <b>conn</b> 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;
+ }
+ }
+}
+
+/** Count moribund connections for the OOS handler */
+MOCK_IMPL(int,
+connection_count_moribund, (void))
+{
+ int moribund = 0;
+
+ /*
+ * Count things we'll try to kill when close_closeable_connections()
+ * runs next.
+ */
+ SMARTLIST_FOREACH_BEGIN(closeable_connection_lst, connection_t *, conn) {
+ if (SOCKET_OK(conn->s) && connection_is_moribund(conn)) ++moribund;
+ } SMARTLIST_FOREACH_END(conn);
+
+ return moribund;
+}
+
+/** Libevent callback: this gets invoked when (connection_t*)<b>conn</b> 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 /* !defined(_WIN32) */
+ 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*)<b>conn</b> 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(); */
+
+ 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 ((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 = buf_move_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 = buf_flush_to_tls(conn->outbuf, TO_OR_CONN(conn)->tls, sz,
+ &conn->outbuf_flushlen);
+ } else
+ retval = -1; /* never flush non-open broken tls connections */
+ } else {
+ retval = buf_flush_to_socket(conn->outbuf, conn->s, 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_last_write_allowed = 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.
+ */
+ connection_consider_empty_read_buckets(conn);
+ connection_consider_empty_write_buckets(conn);
+
+ /* Make sure that consider_empty_buckets really disabled the
+ * connection: */
+ if (BUG(connection_is_writing(conn))) {
+ connection_write_bw_exhausted(conn, true);
+ }
+ if (BUG(connection_is_reading(conn))) {
+ /* XXXX+ 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 */
+ connection_read_bw_exhausted(conn, true/* kludge. */);
+ }
+ }
+ 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);
+ }
+ }
+
+ connection_unlink(conn); /* unlink, remove, free */
+ return 1;
+}
+
+/** Implementation for directory_all_unreachable. This is done in a callback,
+ * since otherwise it would complicate Tor's control-flow graph beyond all
+ * reason.
+ */
+static void
+directory_all_unreachable_cb(mainloop_event_t *event, void *arg)
+{
+ (void)event;
+ (void)arg;
+
+ connection_t *conn;
+
+ 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_error("DIR_ALL_UNREACHABLE");
+}
+
+static mainloop_event_t *directory_all_unreachable_cb_event = NULL;
+
+/** 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)
+{
+ (void)now;
+
+ reset_uptime(); /* reset it */
+
+ if (!directory_all_unreachable_cb_event) {
+ directory_all_unreachable_cb_event =
+ mainloop_event_new(directory_all_unreachable_cb, NULL);
+ tor_assert(directory_all_unreachable_cb_event);
+ }
+
+ mainloop_event_activate(directory_all_unreachable_cb_event);
+}
+
+/** 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, int suppress_logs)
+{
+ const or_options_t *options = get_options();
+
+ /* if we have enough dir info, then update our guard status with
+ * whatever we just learned. */
+ int invalidate_circs = guards_update_all();
+
+ if (invalidate_circs) {
+ circuit_mark_all_unused_circs();
+ circuit_mark_all_dirty_circs_as_unusable();
+ }
+
+ if (!router_have_minimum_dir_info()) {
+ int quiet = suppress_logs || 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);
+ }
+
+ /* 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 &&
+ (have_completed_a_circuit() || !any_predicted_circuits(now)))
+ router_do_reachability_checks(1, 1);
+}
+
+/** 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;
+ channel_t *chan = NULL;
+ int have_any_circuits;
+ int past_keepalive =
+ now >= conn->timestamp_last_write_allowed + 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_last_write_allowed
+ + options->TestingDirConnectionMaxStall < now) ||
+ (!DIR_CONN_IS_SERVER(conn) &&
+ conn->timestamp_last_read_allowed
+ + 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 flushed to an OR connection for a while, then either nuke
+ the connection or send a keepalive, depending. */
+
+ or_conn = TO_OR_CONN(conn);
+ tor_assert(conn->outbuf);
+
+ chan = TLS_CHAN_TO_BASE(or_conn->chan);
+ tor_assert(chan);
+
+ if (channel_num_circuits(chan) != 0) {
+ have_any_circuits = 1;
+ chan->timestamp_last_had_circuits = now;
+ } else {
+ have_any_circuits = 0;
+ }
+
+ if (channel_is_bad_for_new_circs(TLS_CHAN_TO_BASE(or_conn->chan)) &&
+ ! have_any_circuits) {
+ /* 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() &&
+ ! have_any_circuits &&
+ !connection_get_outbuf_len(conn)) {
+ /* We're hibernating or shutting down, 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 (!have_any_circuits &&
+ now - or_conn->idle_timeout >=
+ chan->timestamp_last_had_circuits) {
+ log_info(LD_OR,"Expiring non-used OR connection %"PRIu64" to fd %d "
+ "(%s:%d) [no circuits for %d; timeout %d; %scanonical].",
+ (chan->global_identifier),
+ (int)conn->s, conn->address, conn->port,
+ (int)(now - chan->timestamp_last_had_circuits),
+ or_conn->idle_timeout,
+ or_conn->is_canonical ? "" : "non");
+ connection_or_close_normally(TO_OR_CONN(conn), 0);
+ } else if (
+ now >= or_conn->timestamp_lastempty + options->KeepalivePeriod*10 &&
+ now >=
+ conn->timestamp_last_write_allowed + 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_last_write_allowed));
+ 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);
+ } else {
+ channelpadding_decide_to_pad_channel(chan);
+ }
+}
+
+/** 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();
+ hs_client_purge_state();
+ time_of_last_signewnym = now;
+ signewnym_is_pending = 0;
+
+ ++newnym_epoch;
+
+ control_event_signal(SIGNEWNYM);
+}
+
+/** Callback: run a deferred signewnym. */
+static void
+handle_deferred_signewnym_cb(mainloop_event_t *event, void *arg)
+{
+ (void)event;
+ (void)arg;
+ log_info(LD_CONTROL, "Honoring delayed NEWNYM request");
+ do_signewnym(time(NULL));
+}
+
+/** Either perform a signewnym or schedule one, depending on rate limiting. */
+void
+do_signewnym(time_t now)
+{
+ if (time_of_last_signewnym + MAX_SIGNEWNYM_RATE > now) {
+ const time_t delay_sec =
+ time_of_last_signewnym + MAX_SIGNEWNYM_RATE - now;
+ if (! signewnym_is_pending) {
+ signewnym_is_pending = 1;
+ if (!handle_deferred_signewnym_ev) {
+ handle_deferred_signewnym_ev =
+ mainloop_event_postloop_new(handle_deferred_signewnym_cb, NULL);
+ }
+ const struct timeval delay_tv = { delay_sec, 0 };
+ mainloop_event_schedule(handle_deferred_signewnym_ev, &delay_tv);
+ }
+ log_notice(LD_CONTROL,
+ "Rate limiting NEWNYM request: delaying by %d second(s)",
+ (int)(delay_sec));
+ } else {
+ signewnym_impl(now);
+ }
+}
+
+/** Return the number of times that signewnym has been called. */
+unsigned
+get_signewnym_epoch(void)
+{
+ return newnym_epoch;
+}
+
+/** True iff we have initialized all the members of <b>periodic_events</b>.
+ * Used to prevent double-initialization. */
+static int periodic_events_initialized = 0;
+
+/* Declare all the timer callback functions... */
+#undef CALLBACK
+#define CALLBACK(name) \
+ static int name ## _callback(time_t, const or_options_t *)
+CALLBACK(add_entropy);
+CALLBACK(check_authority_cert);
+CALLBACK(check_canonical_channels);
+CALLBACK(check_descriptor);
+CALLBACK(check_dns_honesty);
+CALLBACK(check_ed_keys);
+CALLBACK(check_expired_networkstatus);
+CALLBACK(check_for_reachability_bw);
+CALLBACK(check_onion_keys_expiry_time);
+CALLBACK(clean_caches);
+CALLBACK(clean_consdiffmgr);
+CALLBACK(dirvote);
+CALLBACK(downrate_stability);
+CALLBACK(expire_old_ciruits_serverside);
+CALLBACK(fetch_networkstatus);
+CALLBACK(heartbeat);
+CALLBACK(hs_service);
+CALLBACK(launch_descriptor_fetches);
+CALLBACK(launch_reachability_tests);
+CALLBACK(reachability_warnings);
+CALLBACK(record_bridge_stats);
+CALLBACK(rend_cache_failure_clean);
+CALLBACK(reset_padding_counts);
+CALLBACK(retry_dns);
+CALLBACK(retry_listeners);
+CALLBACK(rotate_onion_key);
+CALLBACK(rotate_x509_certificate);
+CALLBACK(save_stability);
+CALLBACK(save_state);
+CALLBACK(write_bridge_ns);
+CALLBACK(write_stats_file);
+
+#undef CALLBACK
+
+/* Now we declare an array of periodic_event_item_t for each periodic event */
+#define CALLBACK(name, r, f) PERIODIC_EVENT(name, r, f)
+
+STATIC periodic_event_item_t periodic_events[] = {
+ /* Everyone needs to run those. */
+ CALLBACK(add_entropy, PERIODIC_EVENT_ROLE_ALL, 0),
+ CALLBACK(check_expired_networkstatus, PERIODIC_EVENT_ROLE_ALL, 0),
+ CALLBACK(clean_caches, PERIODIC_EVENT_ROLE_ALL, 0),
+ CALLBACK(fetch_networkstatus, PERIODIC_EVENT_ROLE_ALL,
+ PERIODIC_EVENT_FLAG_NEED_NET),
+ CALLBACK(heartbeat, PERIODIC_EVENT_ROLE_ALL, 0),
+ CALLBACK(launch_descriptor_fetches, PERIODIC_EVENT_ROLE_ALL,
+ PERIODIC_EVENT_FLAG_NEED_NET),
+ CALLBACK(reset_padding_counts, PERIODIC_EVENT_ROLE_ALL, 0),
+ CALLBACK(retry_listeners, PERIODIC_EVENT_ROLE_ALL,
+ PERIODIC_EVENT_FLAG_NEED_NET),
+ CALLBACK(save_state, PERIODIC_EVENT_ROLE_ALL, 0),
+ CALLBACK(rotate_x509_certificate, PERIODIC_EVENT_ROLE_ALL, 0),
+ CALLBACK(write_stats_file, PERIODIC_EVENT_ROLE_ALL, 0),
+
+ /* Routers (bridge and relay) only. */
+ CALLBACK(check_descriptor, PERIODIC_EVENT_ROLE_ROUTER,
+ PERIODIC_EVENT_FLAG_NEED_NET),
+ CALLBACK(check_ed_keys, PERIODIC_EVENT_ROLE_ROUTER, 0),
+ CALLBACK(check_for_reachability_bw, PERIODIC_EVENT_ROLE_ROUTER,
+ PERIODIC_EVENT_FLAG_NEED_NET),
+ CALLBACK(check_onion_keys_expiry_time, PERIODIC_EVENT_ROLE_ROUTER, 0),
+ CALLBACK(expire_old_ciruits_serverside, PERIODIC_EVENT_ROLE_ROUTER,
+ PERIODIC_EVENT_FLAG_NEED_NET),
+ CALLBACK(reachability_warnings, PERIODIC_EVENT_ROLE_ROUTER,
+ PERIODIC_EVENT_FLAG_NEED_NET),
+ CALLBACK(retry_dns, PERIODIC_EVENT_ROLE_ROUTER, 0),
+ CALLBACK(rotate_onion_key, PERIODIC_EVENT_ROLE_ROUTER, 0),
+
+ /* Authorities (bridge and directory) only. */
+ CALLBACK(downrate_stability, PERIODIC_EVENT_ROLE_AUTHORITIES, 0),
+ CALLBACK(launch_reachability_tests, PERIODIC_EVENT_ROLE_AUTHORITIES,
+ PERIODIC_EVENT_FLAG_NEED_NET),
+ CALLBACK(save_stability, PERIODIC_EVENT_ROLE_AUTHORITIES, 0),
+
+ /* Directory authority only. */
+ CALLBACK(check_authority_cert, PERIODIC_EVENT_ROLE_DIRAUTH, 0),
+ CALLBACK(dirvote, PERIODIC_EVENT_ROLE_DIRAUTH, PERIODIC_EVENT_FLAG_NEED_NET),
+
+ /* Relay only. */
+ CALLBACK(check_canonical_channels, PERIODIC_EVENT_ROLE_RELAY,
+ PERIODIC_EVENT_FLAG_NEED_NET),
+ CALLBACK(check_dns_honesty, PERIODIC_EVENT_ROLE_RELAY,
+ PERIODIC_EVENT_FLAG_NEED_NET),
+
+ /* Hidden Service service only. */
+ CALLBACK(hs_service, PERIODIC_EVENT_ROLE_HS_SERVICE,
+ PERIODIC_EVENT_FLAG_NEED_NET),
+
+ /* Bridge only. */
+ CALLBACK(record_bridge_stats, PERIODIC_EVENT_ROLE_BRIDGE, 0),
+
+ /* Client only. */
+ CALLBACK(rend_cache_failure_clean, PERIODIC_EVENT_ROLE_CLIENT, 0),
+
+ /* Bridge Authority only. */
+ CALLBACK(write_bridge_ns, PERIODIC_EVENT_ROLE_BRIDGEAUTH, 0),
+
+ /* Directory server only. */
+ CALLBACK(clean_consdiffmgr, PERIODIC_EVENT_ROLE_DIRSERVER, 0),
+
+ END_OF_PERIODIC_EVENTS
+};
+#undef CALLBACK
+
+/* These are pointers to members of periodic_events[] that are used to
+ * implement particular callbacks. We keep them separate here so that we
+ * can access them by name. We also keep them inside periodic_events[]
+ * so that we can implement "reset all timers" in a reasonable way. */
+static periodic_event_item_t *check_descriptor_event=NULL;
+static periodic_event_item_t *dirvote_event=NULL;
+static periodic_event_item_t *fetch_networkstatus_event=NULL;
+static periodic_event_item_t *launch_descriptor_fetches_event=NULL;
+static periodic_event_item_t *check_dns_honesty_event=NULL;
+static periodic_event_item_t *save_state_event=NULL;
+
+/** Reset all the periodic events so we'll do all our actions again as if we
+ * just started up.
+ * Useful if our clock just moved back a long time from the future,
+ * so we don't wait until that future arrives again before acting.
+ */
+void
+reset_all_main_loop_timers(void)
+{
+ int i;
+ for (i = 0; periodic_events[i].name; ++i) {
+ periodic_event_reschedule(&periodic_events[i]);
+ }
+}
+
+/** Return the member of periodic_events[] whose name is <b>name</b>.
+ * Return NULL if no such event is found.
+ */
+static periodic_event_item_t *
+find_periodic_event(const char *name)
+{
+ int i;
+ for (i = 0; periodic_events[i].name; ++i) {
+ if (strcmp(name, periodic_events[i].name) == 0)
+ return &periodic_events[i];
+ }
+ return NULL;
+}
+
+/** Return a bitmask of the roles this tor instance is configured for using
+ * the given options. */
+STATIC int
+get_my_roles(const or_options_t *options)
+{
+ tor_assert(options);
+
+ int roles = 0;
+ int is_bridge = options->BridgeRelay;
- int is_client = options_any_client_port_set(options);
+ int is_relay = server_mode(options);
+ int is_dirauth = authdir_mode_v3(options);
+ int is_bridgeauth = authdir_mode_bridge(options);
+ int is_hidden_service = !!hs_service_get_num_services() ||
+ !!rend_num_services();
+ int is_dirserver = dir_server_mode(options);
++ /* We also consider tor to have the role of a client if the ControlPort is
++ * set because a lot of things can be done over the control port which
++ * requires tor to have basic functionnalities. */
++ int is_client = options_any_client_port_set(options) ||
++ options->ControlPort_set ||
++ options->OwningControllerFD >= 0;
+
+ if (is_bridge) roles |= PERIODIC_EVENT_ROLE_BRIDGE;
+ if (is_client) roles |= PERIODIC_EVENT_ROLE_CLIENT;
+ if (is_relay) roles |= PERIODIC_EVENT_ROLE_RELAY;
+ if (is_dirauth) roles |= PERIODIC_EVENT_ROLE_DIRAUTH;
+ if (is_bridgeauth) roles |= PERIODIC_EVENT_ROLE_BRIDGEAUTH;
+ if (is_hidden_service) roles |= PERIODIC_EVENT_ROLE_HS_SERVICE;
+ if (is_dirserver) roles |= PERIODIC_EVENT_ROLE_DIRSERVER;
+
+ return roles;
+}
+
+/** Event to run initialize_periodic_events_cb */
+static struct event *initialize_periodic_events_event = NULL;
+
+/** Helper, run one second after setup:
+ * Initializes all members of periodic_events and starts them running.
+ *
+ * (We do this one second after setup for backward-compatibility reasons;
+ * it might not actually be necessary.) */
+static void
+initialize_periodic_events_cb(evutil_socket_t fd, short events, void *data)
+{
+ (void) fd;
+ (void) events;
+ (void) data;
+
+ tor_event_free(initialize_periodic_events_event);
+
+ rescan_periodic_events(get_options());
+}
+
+/** Set up all the members of periodic_events[], and configure them all to be
+ * launched from a callback. */
+STATIC void
+initialize_periodic_events(void)
+{
+ if (periodic_events_initialized)
+ return;
+
+ periodic_events_initialized = 1;
+
+ /* Set up all periodic events. We'll launch them by roles. */
+ int i;
+ for (i = 0; periodic_events[i].name; ++i) {
+ periodic_event_setup(&periodic_events[i]);
+ }
+
+#define NAMED_CALLBACK(name) \
+ STMT_BEGIN name ## _event = find_periodic_event( #name ); STMT_END
+
+ NAMED_CALLBACK(check_descriptor);
+ NAMED_CALLBACK(dirvote);
+ NAMED_CALLBACK(fetch_networkstatus);
+ NAMED_CALLBACK(launch_descriptor_fetches);
+ NAMED_CALLBACK(check_dns_honesty);
+ NAMED_CALLBACK(save_state);
+
+ struct timeval one_second = { 1, 0 };
+ initialize_periodic_events_event = tor_evtimer_new(
+ tor_libevent_get_base(),
+ initialize_periodic_events_cb, NULL);
+ event_add(initialize_periodic_events_event, &one_second);
+}
+
+STATIC void
+teardown_periodic_events(void)
+{
+ int i;
+ for (i = 0; periodic_events[i].name; ++i) {
+ periodic_event_destroy(&periodic_events[i]);
+ }
+ periodic_events_initialized = 0;
+}
+
+/** Do a pass at all our periodic events, disable those we don't need anymore
+ * and enable those we need now using the given options. */
+void
+rescan_periodic_events(const or_options_t *options)
+{
+ tor_assert(options);
+
+ /* Avoid scanning the event list if we haven't initialized it yet. This is
+ * particularly useful for unit tests in order to avoid initializing main
+ * loop events everytime. */
+ if (!periodic_events_initialized) {
+ return;
+ }
+
+ int roles = get_my_roles(options);
+
+ for (int i = 0; periodic_events[i].name; ++i) {
+ periodic_event_item_t *item = &periodic_events[i];
+
+ /* Handle the event flags. */
+ if (net_is_disabled() &&
+ (item->flags & PERIODIC_EVENT_FLAG_NEED_NET)) {
+ continue;
+ }
+
+ /* Enable the event if needed. It is safe to enable an event that was
+ * already enabled. Same goes for disabling it. */
+ if (item->roles & roles) {
+ log_debug(LD_GENERAL, "Launching periodic event %s", item->name);
+ periodic_event_enable(item);
+ } else {
+ log_debug(LD_GENERAL, "Disabling periodic event %s", item->name);
+ periodic_event_disable(item);
+ }
+ }
+}
+
+/* We just got new options globally set, see if we need to enabled or disable
+ * periodic events. */
+void
+periodic_events_on_new_options(const or_options_t *options)
+{
+ /* Only if we've already initialized the events, rescan the list which will
+ * enable or disable events depending on our roles. This will be called at
+ * bootup and we don't want this function to initialize the events because
+ * they aren't set up at this stage. */
+ if (periodic_events_initialized) {
+ rescan_periodic_events(options);
+ }
+}
+
+/**
+ * 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)
+{
+ if (check_descriptor_event) {
+ periodic_event_reschedule(check_descriptor_event);
+ }
+}
+
+/**
+ * Update our schedule so that we'll check whether we need to fetch directory
+ * info immediately.
+ */
+void
+reschedule_directory_downloads(void)
+{
+ tor_assert(fetch_networkstatus_event);
+ tor_assert(launch_descriptor_fetches_event);
+
+ periodic_event_reschedule(fetch_networkstatus_event);
+ periodic_event_reschedule(launch_descriptor_fetches_event);
+}
+
+/** Mainloop callback: clean up circuits, channels, and connections
+ * that are pending close. */
+static void
+postloop_cleanup_cb(mainloop_event_t *ev, void *arg)
+{
+ (void)ev;
+ (void)arg;
+ circuit_close_all_marked();
+ close_closeable_connections();
+ channel_run_cleanup();
+ channel_listener_run_cleanup();
+}
+
+/** Event to run postloop_cleanup_cb */
+static mainloop_event_t *postloop_cleanup_ev=NULL;
+
+/** Schedule a post-loop event to clean up marked channels, connections, and
+ * circuits. */
+void
+mainloop_schedule_postloop_cleanup(void)
+{
+ if (PREDICT_UNLIKELY(postloop_cleanup_ev == NULL)) {
+ // (It's possible that we can get here if we decide to close a connection
+ // in the earliest stages of our configuration, before we create events.)
+ return;
+ }
+ mainloop_event_activate(postloop_cleanup_ev);
+}
+
+#define LONGEST_TIMER_PERIOD (30 * 86400)
+/** Helper: Return the number of seconds between <b>now</b> and <b>next</b>,
+ * clipped to the range [1 second, LONGEST_TIMER_PERIOD]. */
+static inline int
+safe_timer_diff(time_t now, time_t next)
+{
+ if (next > now) {
+ /* There were no computers at signed TIME_MIN (1902 on 32-bit systems),
+ * and nothing that could run Tor. It's a bug if 'next' is around then.
+ * On 64-bit systems with signed TIME_MIN, TIME_MIN is before the Big
+ * Bang. We cannot extrapolate past a singularity, but there was probably
+ * nothing that could run Tor then, either.
+ **/
+ tor_assert(next > TIME_MIN + LONGEST_TIMER_PERIOD);
+
+ if (next - LONGEST_TIMER_PERIOD > now)
+ return LONGEST_TIMER_PERIOD;
+ return (int)(next - now);
+ } else {
+ return 1;
+ }
+}
+
+/** Perform regular maintenance tasks. This function gets run once per
+ * second by second_elapsed_callback().
+ */
+static void
+run_scheduled_events(time_t now)
+{
+ const or_options_t *options = get_options();
+
+ /* 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);
+
+ /* Maybe enough time elapsed for us to reconsider a circuit. */
+ circuit_upgrade_circuits_from_guard_wait();
+
+ if (options->UseBridges && !net_is_disabled()) {
+ /* Note: this check uses net_is_disabled(), not should_delay_dir_fetches()
+ * -- the latter is only for fetching consensus-derived directory info. */
+ fetch_bridge_descriptors(options, now);
+ }
+
+ if (accounting_is_enabled(options)) {
+ accounting_run_housekeeping(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();
+ circuit_expire_waiting_for_better_guard();
+
+ /* 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();
+
+ /* 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.
+ */
+ const int have_dir_info = router_have_minimum_dir_info();
+ if (have_dir_info && !net_is_disabled()) {
+ circuit_build_needed_circs(now);
+ } else {
+ circuit_expire_old_circs_as_needed(now);
+ }
+
+ /* 5. We do housekeeping for each connection... */
+ channel_update_bad_for_new_circs(NULL, 0);
+ int i;
+ for (i=0;i<smartlist_len(connection_array);i++) {
+ run_connection_housekeeping(i, now);
+ }
+
+ /* 11b. check pending unconfigured managed proxies */
+ if (!net_is_disabled() && pt_proxies_configuration_pending())
+ pt_configure_remaining_proxies();
+}
+
+/* Periodic callback: rotate the onion keys after the period defined by the
+ * "onion-key-rotation-days" consensus parameter, shut down and restart all
+ * cpuworkers, and update our descriptor if necessary.
+ */
+static int
+rotate_onion_key_callback(time_t now, const or_options_t *options)
+{
+ if (server_mode(options)) {
+ int onion_key_lifetime = get_onion_key_lifetime();
+ time_t rotation_time = get_onion_key_set_at()+onion_key_lifetime;
+ if (rotation_time > now) {
+ return ONION_KEY_CONSENSUS_CHECK_INTERVAL;
+ }
+
+ log_info(LD_GENERAL,"Rotating onion key.");
+ rotate_onion_key();
+ cpuworkers_rotate_keyinfo();
+ if (router_rebuild_descriptor(1)<0) {
+ log_info(LD_CONFIG, "Couldn't rebuild router descriptor");
+ }
+ if (advertised_server_mode() && !net_is_disabled())
+ router_upload_dir_desc_to_dirservers(0);
+ return ONION_KEY_CONSENSUS_CHECK_INTERVAL;
+ }
+ return PERIODIC_EVENT_NO_UPDATE;
+}
+
+/* Period callback: Check if our old onion keys are still valid after the
+ * period of time defined by the consensus parameter
+ * "onion-key-grace-period-days", otherwise expire them by setting them to
+ * NULL.
+ */
+static int
+check_onion_keys_expiry_time_callback(time_t now, const or_options_t *options)
+{
+ if (server_mode(options)) {
+ int onion_key_grace_period = get_onion_key_grace_period();
+ time_t expiry_time = get_onion_key_set_at()+onion_key_grace_period;
+ if (expiry_time > now) {
+ return ONION_KEY_CONSENSUS_CHECK_INTERVAL;
+ }
+
+ log_info(LD_GENERAL, "Expiring old onion keys.");
+ expire_old_onion_keys();
+ cpuworkers_rotate_keyinfo();
+ return ONION_KEY_CONSENSUS_CHECK_INTERVAL;
+ }
+
+ return PERIODIC_EVENT_NO_UPDATE;
+}
+
+/* Periodic callback: Every 30 seconds, check whether it's time to make new
+ * Ed25519 subkeys.
+ */
+static int
+check_ed_keys_callback(time_t now, const or_options_t *options)
+{
+ if (server_mode(options)) {
+ if (should_make_new_ed_keys(options, now)) {
+ int new_signing_key = load_ed_keys(options, now);
+ if (new_signing_key < 0 ||
+ generate_ed_link_cert(options, now, new_signing_key > 0)) {
+ log_err(LD_OR, "Unable to update Ed25519 keys! Exiting.");
+ tor_shutdown_event_loop_and_exit(1);
+ }
+ }
+ return 30;
+ }
+ return PERIODIC_EVENT_NO_UPDATE;
+}
+
+/**
+ * Periodic callback: Every {LAZY,GREEDY}_DESCRIPTOR_RETRY_INTERVAL,
+ * see about fetching descriptors, microdescriptors, and extrainfo
+ * documents.
+ */
+static int
+launch_descriptor_fetches_callback(time_t now, const or_options_t *options)
+{
+ if (should_delay_dir_fetches(options, NULL))
+ return PERIODIC_EVENT_NO_UPDATE;
+
+ update_all_descriptor_downloads(now);
+ update_extrainfo_downloads(now);
+ if (router_have_minimum_dir_info())
+ return LAZY_DESCRIPTOR_RETRY_INTERVAL;
+ else
+ return GREEDY_DESCRIPTOR_RETRY_INTERVAL;
+}
+
+/**
+ * Periodic event: Rotate our X.509 certificates and TLS keys once every
+ * MAX_SSL_KEY_LIFETIME_INTERNAL.
+ */
+static int
+rotate_x509_certificate_callback(time_t now, const or_options_t *options)
+{
+ static int first = 1;
+ (void)now;
+ (void)options;
+ if (first) {
+ first = 0;
+ return MAX_SSL_KEY_LIFETIME_INTERNAL;
+ }
+
+ /* 1b. Every MAX_SSL_KEY_LIFETIME_INTERNAL seconds, we change our
+ * TLS context. */
+ log_info(LD_GENERAL,"Rotating tls context.");
+ if (router_initialize_tls_context() < 0) {
+ log_err(LD_BUG, "Error reinitializing TLS context");
+ tor_assert_unreached();
+ }
+ if (generate_ed_link_cert(options, now, 1)) {
+ log_err(LD_OR, "Unable to update Ed25519->TLS link certificate for "
+ "new TLS context.");
+ tor_assert_unreached();
+ }
+
+ /* 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
+ * run_connection_housekeeping() above. */
+ return MAX_SSL_KEY_LIFETIME_INTERNAL;
+}
+
+/**
+ * Periodic callback: once an hour, grab some more entropy from the
+ * kernel and feed it to our CSPRNG.
+ **/
+static int
+add_entropy_callback(time_t now, const or_options_t *options)
+{
+ (void)now;
+ (void)options;
+ /* We already seeded once, so don't die on failure. */
+ if (crypto_seed_rng() < 0) {
+ log_warn(LD_GENERAL, "Tried to re-seed RNG, but failed. We already "
+ "seeded once, though, so we won't exit here.");
+ }
+
+ /** How often do we add more entropy to OpenSSL's RNG pool? */
+#define ENTROPY_INTERVAL (60*60)
+ return ENTROPY_INTERVAL;
+}
+
+/**
+ * Periodic callback: if we're an authority, make sure we test
+ * the routers on the network for reachability.
+ */
+static int
+launch_reachability_tests_callback(time_t now, const or_options_t *options)
+{
+ if (authdir_mode_tests_reachability(options) &&
+ !net_is_disabled()) {
+ /* try to determine reachability of the other Tor relays */
+ dirserv_test_reachability(now);
+ }
+ return REACHABILITY_TEST_INTERVAL;
+}
+
+/**
+ * Periodic callback: if we're an authority, discount the stability
+ * information (and other rephist information) that's older.
+ */
+static int
+downrate_stability_callback(time_t now, const or_options_t *options)
+{
+ (void)options;
+ /* 1d. Periodically, we discount older stability information so that new
+ * stability info counts more, and save the stability information to disk as
+ * appropriate. */
+ time_t next = rep_hist_downrate_old_runs(now);
+ return safe_timer_diff(now, next);
+}
+
+/**
+ * Periodic callback: if we're an authority, record our measured stability
+ * information from rephist in an mtbf file.
+ */
+static int
+save_stability_callback(time_t now, const or_options_t *options)
+{
+ if (authdir_mode_tests_reachability(options)) {
+ if (rep_hist_record_mtbf_data(now, 1)<0) {
+ log_warn(LD_GENERAL, "Couldn't store mtbf data.");
+ }
+ }
+#define SAVE_STABILITY_INTERVAL (30*60)
+ return SAVE_STABILITY_INTERVAL;
+}
+
+/**
+ * Periodic callback: if we're an authority, check on our authority
+ * certificate (the one that authenticates our authority signing key).
+ */
+static int
+check_authority_cert_callback(time_t now, const or_options_t *options)
+{
+ (void)now;
+ (void)options;
+ /* 1e. Periodically, if we're a v3 authority, we check whether our cert is
+ * close to expiring and warn the admin if it is. */
+ v3_authority_check_key_expiry();
+#define CHECK_V3_CERTIFICATE_INTERVAL (5*60)
+ return CHECK_V3_CERTIFICATE_INTERVAL;
+}
+
+/**
+ * Scheduled callback: Run directory-authority voting functionality.
+ *
+ * The schedule is a bit complicated here, so dirvote_act() manages the
+ * schedule itself.
+ **/
+static int
+dirvote_callback(time_t now, const or_options_t *options)
+{
+ if (!authdir_mode_v3(options)) {
+ tor_assert_nonfatal_unreached();
+ return 3600;
+ }
+
+ time_t next = dirvote_act(options, now);
+ if (BUG(next == TIME_MAX)) {
+ /* This shouldn't be returned unless we called dirvote_act() without
+ * being an authority. If it happens, maybe our configuration will
+ * fix itself in an hour or so? */
+ return 3600;
+ }
+ return safe_timer_diff(now, next);
+}
+
+/** Reschedule the directory-authority voting event. Run this whenever the
+ * schedule has changed. */
+void
+reschedule_dirvote(const or_options_t *options)
+{
+ if (periodic_events_initialized && authdir_mode_v3(options)) {
+ periodic_event_reschedule(dirvote_event);
+ }
+}
+
+/**
+ * Periodic callback: If our consensus is too old, recalculate whether
+ * we can actually use it.
+ */
+static int
+check_expired_networkstatus_callback(time_t now, const or_options_t *options)
+{
+ (void)options;
+ /* Check whether our networkstatus has expired. */
+ 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)
+ return CHECK_EXPIRED_NS_INTERVAL;
+}
+
+/**
+ * Scheduled callback: Save the state file to disk if appropriate.
+ */
+static int
+save_state_callback(time_t now, const or_options_t *options)
+{
+ (void) options;
+ (void) or_state_save(now); // only saves if appropriate
+ const time_t next_write = get_or_state()->next_write;
+ if (next_write == TIME_MAX) {
+ return 86400;
+ }
+ return safe_timer_diff(now, next_write);
+}
+
+/** Reschedule the event for saving the state file.
+ *
+ * Run this when the state becomes dirty. */
+void
+reschedule_or_state_save(void)
+{
+ if (save_state_event == NULL) {
+ /* This can happen early on during startup. */
+ return;
+ }
+ periodic_event_reschedule(save_state_event);
+}
+
+/**
+ * Periodic callback: Write statistics to disk if appropriate.
+ */
+static int
+write_stats_file_callback(time_t now, const or_options_t *options)
+{
+ /* 1g. Check whether we should write statistics to disk.
+ */
+#define CHECK_WRITE_STATS_INTERVAL (60*60)
+ time_t next_time_to_write_stats_files = now + CHECK_WRITE_STATS_INTERVAL;
+ if (options->CellStatistics) {
+ time_t next_write =
+ rep_hist_buffer_stats_write(now);
+ 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(now);
+ 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(now);
+ if (next_write && next_write < next_time_to_write_stats_files)
+ next_time_to_write_stats_files = next_write;
+ }
+ if (options->HiddenServiceStatistics) {
+ time_t next_write = rep_hist_hs_stats_write(now);
+ 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(now);
+ 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(now);
+ 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(now);
+ if (next_write && next_write < next_time_to_write_stats_files)
+ next_time_to_write_stats_files = next_write;
+ }
+
+ return safe_timer_diff(now, next_time_to_write_stats_files);
+}
+
+#define CHANNEL_CHECK_INTERVAL (60*60)
+static int
+check_canonical_channels_callback(time_t now, const or_options_t *options)
+{
+ (void)now;
+ if (public_server_mode(options))
+ channel_check_for_duplicates();
+
+ return CHANNEL_CHECK_INTERVAL;
+}
+
+static int
+reset_padding_counts_callback(time_t now, const or_options_t *options)
+{
+ if (options->PaddingStatistics) {
+ rep_hist_prep_published_padding_counts(now);
+ }
+
+ rep_hist_reset_padding_counts();
+ return REPHIST_CELL_PADDING_COUNTS_INTERVAL;
+}
+
+static int should_init_bridge_stats = 1;
+
+/**
+ * Periodic callback: Write bridge statistics to disk if appropriate.
+ */
+static int
+record_bridge_stats_callback(time_t now, const or_options_t *options)
+{
+ /* 1h. Check whether we should write bridge statistics to disk.
+ */
+ if (should_record_bridge_info(options)) {
+ if (should_init_bridge_stats) {
+ /* (Re-)initialize bridge statistics. */
+ geoip_bridge_stats_init(now);
+ should_init_bridge_stats = 0;
+ return WRITE_STATS_INTERVAL;
+ } else {
+ /* Possibly write bridge statistics to disk and ask when to write
+ * them next time. */
+ time_t next = geoip_bridge_stats_write(now);
+ return safe_timer_diff(now, next);
+ }
+ } 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;
+ }
+ return PERIODIC_EVENT_NO_UPDATE;
+}
+
+/**
+ * Periodic callback: Clean in-memory caches every once in a while
+ */
+static int
+clean_caches_callback(time_t now, const or_options_t *options)
+{
+ /* Remove old information from rephist and the rend cache. */
+ rep_history_clean(now - options->RephistTrackTime);
+ rend_cache_clean(now, REND_CACHE_TYPE_SERVICE);
+ hs_cache_clean_as_client(now);
+ hs_cache_clean_as_dir(now);
+ microdesc_cache_rebuild(NULL, 0);
+#define CLEAN_CACHES_INTERVAL (30*60)
+ return CLEAN_CACHES_INTERVAL;
+}
+
+/**
+ * Periodic callback: Clean the cache of failed hidden service lookups
+ * frequently.
+ */
+static int
+rend_cache_failure_clean_callback(time_t now, const or_options_t *options)
+{
+ (void)options;
+ /* We don't keep entries that are more than five minutes old so we try to
+ * clean it as soon as we can since we want to make sure the client waits
+ * as little as possible for reachability reasons. */
+ rend_cache_failure_clean(now);
+ hs_cache_client_intro_state_clean(now);
+ return 30;
+}
+
+/**
+ * Periodic callback: If we're a server and initializing dns failed, retry.
+ */
+static int
+retry_dns_callback(time_t now, const or_options_t *options)
+{
+ (void)now;
+#define RETRY_DNS_INTERVAL (10*60)
+ if (server_mode(options) && has_dns_init_failed())
+ dns_init();
+ return RETRY_DNS_INTERVAL;
+}
+
+/** Periodic callback: consider rebuilding or and re-uploading our descriptor
+ * (if we've passed our internal checks). */
+static int
+check_descriptor_callback(time_t now, const or_options_t *options)
+{
+/** 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)
+
+ (void)options;
+
+ /* 2b. Once per minute, regenerate and upload the descriptor if the old
+ * one is inaccurate. */
+ if (!net_is_disabled()) {
+ check_descriptor_bandwidth_changed(now);
+ check_descriptor_ipaddress_changed(now);
+ mark_my_descriptor_dirty_if_too_old(now);
+ consider_publishable_server(0);
+ /* If any networkstatus documents are no longer recent, we need to
+ * update all the descriptors' running status. */
+ /* Remove dead routers. */
+ /* XXXX This doesn't belong here, but it was here in the pre-
+ * XXXX refactoring code. */
+ routerlist_remove_old_routers();
+ }
+
+ return CHECK_DESCRIPTOR_INTERVAL;
+}
+
+/**
+ * Periodic callback: check whether we're reachable (as a relay), and
+ * whether our bandwidth has changed enough that we need to
+ * publish a new descriptor.
+ */
+static int
+check_for_reachability_bw_callback(time_t now, const or_options_t *options)
+{
+ /* XXXX This whole thing was stuck in the middle of what is now
+ * XXXX check_descriptor_callback. I'm not sure it's right. */
+
+ static int dirport_reachability_count = 0;
+ /* also, check religiously for reachability, if it's within the first
+ * 20 minutes of our uptime. */
+ if (server_mode(options) &&
+ (have_completed_a_circuit() || !any_predicted_circuits(now)) &&
+ !net_is_disabled()) {
+ if (get_uptime() < TIMEOUT_UNTIL_UNREACHABILITY_COMPLAINT) {
+ router_do_reachability_checks(1, dirport_reachability_count==0);
+ if (++dirport_reachability_count > 5)
+ dirport_reachability_count = 0;
+ return 1;
+ } else {
+ /* 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();
+ static int first_time = 1;
+ if (!first_time && me &&
+ me->bandwidthcapacity < me->bandwidthrate &&
+ me->bandwidthcapacity < 51200) {
+ reset_bandwidth_test();
+ }
+ first_time = 0;
+#define BANDWIDTH_RECHECK_INTERVAL (12*60*60)
+ return BANDWIDTH_RECHECK_INTERVAL;
+ }
+ }
+ return CHECK_DESCRIPTOR_INTERVAL;
+}
+
+/**
+ * Periodic event: once a minute, (or every second if TestingTorNetwork, or
+ * during client bootstrap), check whether we want to download any
+ * networkstatus documents. */
+static int
+fetch_networkstatus_callback(time_t now, const or_options_t *options)
+{
+ /* How often do we check whether we should download network status
+ * documents? */
+ const int we_are_bootstrapping = networkstatus_consensus_is_bootstrapping(
+ now);
+ const int prefer_mirrors = !directory_fetches_from_authorities(
+ get_options());
+ int networkstatus_dl_check_interval = 60;
+ /* check more often when testing, or when bootstrapping from mirrors
+ * (connection limits prevent too many connections being made) */
+ if (options->TestingTorNetwork
+ || (we_are_bootstrapping && prefer_mirrors)) {
+ networkstatus_dl_check_interval = 1;
+ }
+
+ if (should_delay_dir_fetches(options, NULL))
+ return PERIODIC_EVENT_NO_UPDATE;
+
+ update_networkstatus_downloads(now);
+ return networkstatus_dl_check_interval;
+}
+
+/**
+ * Periodic callback: Every 60 seconds, we relaunch listeners if any died. */
+static int
+retry_listeners_callback(time_t now, const or_options_t *options)
+{
+ (void)now;
+ (void)options;
+ if (!net_is_disabled()) {
+ retry_all_listeners(NULL, 0);
+ return 60;
+ }
+ return PERIODIC_EVENT_NO_UPDATE;
+}
+
+/**
+ * Periodic callback: as a server, see if we have any old unused circuits
+ * that should be expired */
+static int
+expire_old_ciruits_serverside_callback(time_t now, const or_options_t *options)
+{
+ (void)options;
+ /* every 11 seconds, so not usually the same second as other such events */
+ circuit_expire_old_circuits_serverside(now);
+ return 11;
+}
+
+/**
+ * Callback: Send warnings if Tor doesn't find its ports reachable.
+ */
+static int
+reachability_warnings_callback(time_t now, const or_options_t *options)
+{
+ (void) now;
+
+ if (get_uptime() < TIMEOUT_UNTIL_UNREACHABILITY_COMPLAINT) {
+ return (int)(TIMEOUT_UNTIL_UNREACHABILITY_COMPLAINT - get_uptime());
+ }
+
+ if (server_mode(options) &&
+ !net_is_disabled() &&
+ have_completed_a_circuit()) {
+ /* every 20 minutes, check and complain if necessary */
+ const routerinfo_t *me = router_get_my_routerinfo();
+ if (me && !check_whether_orport_reachable(options)) {
+ 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. Relays do not publish descriptors "
+ "until their ORPort and DirPort are 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(options)) {
+ 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. Relays do not publish descriptors "
+ "until their ORPort and DirPort are 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);
+ }
+ }
+
+ return TIMEOUT_UNTIL_UNREACHABILITY_COMPLAINT;
+}
+
+static int dns_honesty_first_time = 1;
+
+/**
+ * Periodic event: if we're an exit, see if our DNS server is telling us
+ * obvious lies.
+ */
+static int
+check_dns_honesty_callback(time_t now, const or_options_t *options)
+{
+ (void)now;
+ /* 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) ||
+ router_my_exit_policy_is_reject_star())
+ return PERIODIC_EVENT_NO_UPDATE;
+
+ if (dns_honesty_first_time) {
+ /* Don't launch right when we start */
+ dns_honesty_first_time = 0;
+ return crypto_rand_int_range(60, 180);
+ }
+
+ dns_launch_correctness_checks();
+ return 12*3600 + crypto_rand_int(12*3600);
+}
+
+/**
+ * Periodic callback: if we're the bridge authority, write a networkstatus
+ * file to disk.
+ */
+static int
+write_bridge_ns_callback(time_t now, const or_options_t *options)
+{
+ /* 10. write bridge networkstatus file to disk */
+ if (options->BridgeAuthoritativeDir) {
+ networkstatus_dump_bridge_status_to_file(now);
+#define BRIDGE_STATUSFILE_INTERVAL (30*60)
+ return BRIDGE_STATUSFILE_INTERVAL;
+ }
+ return PERIODIC_EVENT_NO_UPDATE;
+}
+
+static int heartbeat_callback_first_time = 1;
+
+/**
+ * Periodic callback: write the heartbeat message in the logs.
+ *
+ * If writing the heartbeat message to the logs fails for some reason, retry
+ * again after <b>MIN_HEARTBEAT_PERIOD</b> seconds.
+ */
+static int
+heartbeat_callback(time_t now, const or_options_t *options)
+{
+ /* Check if heartbeat is disabled */
+ if (!options->HeartbeatPeriod) {
+ return PERIODIC_EVENT_NO_UPDATE;
+ }
+
+ /* Skip the first one. */
+ if (heartbeat_callback_first_time) {
+ heartbeat_callback_first_time = 0;
+ return options->HeartbeatPeriod;
+ }
+
+ /* Write the heartbeat message */
+ if (log_heartbeat(now) == 0) {
+ return options->HeartbeatPeriod;
+ } else {
+ /* If we couldn't write the heartbeat log message, try again in the minimum
+ * interval of time. */
+ return MIN_HEARTBEAT_PERIOD;
+ }
+}
+
+#define CDM_CLEAN_CALLBACK_INTERVAL 600
+static int
+clean_consdiffmgr_callback(time_t now, const or_options_t *options)
+{
+ (void)now;
+ if (dir_server_mode(options)) {
+ consdiffmgr_cleanup();
+ }
+ return CDM_CLEAN_CALLBACK_INTERVAL;
+}
+
+/*
+ * Periodic callback: Run scheduled events for HS service. This is called
+ * every second.
+ */
+static int
+hs_service_callback(time_t now, const or_options_t *options)
+{
+ (void) options;
+
+ /* We need to at least be able to build circuits and that we actually have
+ * a working network. */
+ if (!have_completed_a_circuit() || net_is_disabled() ||
+ networkstatus_get_live_consensus(now) == NULL) {
+ goto end;
+ }
+
+ hs_service_run_scheduled_events(now);
+
+ end:
+ /* Every 1 second. */
+ return 1;
+}
+
+/** Timer: used to invoke second_elapsed_callback() once per second. */
+static periodic_timer_t *second_timer = NULL;
+
+/**
+ * Enable or disable the per-second timer as appropriate, creating it if
+ * necessary.
+ */
+void
+reschedule_per_second_timer(void)
+{
+ struct timeval one_second;
+ one_second.tv_sec = 1;
+ one_second.tv_usec = 0;
+
+ if (! second_timer) {
+ second_timer = periodic_timer_new(tor_libevent_get_base(),
+ &one_second,
+ second_elapsed_callback,
+ NULL);
+ tor_assert(second_timer);
+ }
+
+ const bool run_per_second_events =
+ control_any_per_second_event_enabled() || ! net_is_completely_disabled();
+
+ if (run_per_second_events) {
+ periodic_timer_launch(second_timer, &one_second);
+ } else {
+ periodic_timer_disable(second_timer);
+ }
+}
+
+/** Last time that update_current_time was called. */
+static time_t current_second = 0;
+/** Last time that update_current_time updated current_second. */
+static monotime_coarse_t current_second_last_changed;
+
+/**
+ * Set the current time to "now", which should be the value returned by
+ * time(). Check for clock jumps and track the total number of seconds we
+ * have been running.
+ */
+void
+update_current_time(time_t now)
+{
+ if (PREDICT_LIKELY(now == current_second)) {
+ /* We call this function a lot. Most frequently, the current second
+ * will not have changed, so we just return. */
+ return;
+ }
+
+ const time_t seconds_elapsed = current_second ? (now - current_second) : 0;
+
+ /* Check the wall clock against the monotonic clock, so we can
+ * better tell idleness from clock jumps and/or other shenanigans. */
+ monotime_coarse_t last_updated;
+ memcpy(&last_updated, ¤t_second_last_changed, sizeof(last_updated));
+ monotime_coarse_get(¤t_second_last_changed);
+
+ /** How much clock jumping do we tolerate? */
+#define NUM_JUMPED_SECONDS_BEFORE_WARN 100
+
+ /** How much idleness do we tolerate? */
+#define NUM_IDLE_SECONDS_BEFORE_WARN 3600
+
+ if (seconds_elapsed < -NUM_JUMPED_SECONDS_BEFORE_WARN) {
+ // moving back in time is always a bad sign.
+ circuit_note_clock_jumped(seconds_elapsed, false);
+ } else if (seconds_elapsed >= NUM_JUMPED_SECONDS_BEFORE_WARN) {
+ /* Compare the monotonic clock to the result of time(). */
+ const int32_t monotime_msec_passed =
+ monotime_coarse_diff_msec32(&last_updated,
+ ¤t_second_last_changed);
+ const int monotime_sec_passed = monotime_msec_passed / 1000;
+ const int discrepancy = monotime_sec_passed - (int)seconds_elapsed;
+ /* If the monotonic clock deviates from time(NULL), we have a couple of
+ * possibilities. On some systems, this means we have been suspended or
+ * sleeping. Everywhere, it can mean that the wall-clock time has
+ * been changed -- for example, with settimeofday().
+ *
+ * On the other hand, if the monotonic time matches with the wall-clock
+ * time, we've probably just been idle for a while, with no events firing.
+ * we tolerate much more of that.
+ */
+ const bool clock_jumped = abs(discrepancy) > 2;
+
+ if (clock_jumped || seconds_elapsed >= NUM_IDLE_SECONDS_BEFORE_WARN) {
+ circuit_note_clock_jumped(seconds_elapsed, ! clock_jumped);
+ }
+ } else if (seconds_elapsed > 0) {
+ stats_n_seconds_working += seconds_elapsed;
+ }
+
+ update_approx_time(now);
+ current_second = now;
+}
+
+/** 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. */
+ time_t now;
+ (void)timer;
+ (void)arg;
+
+ now = time(NULL);
+
+ /* We don't need to do this once-per-second any more: time-updating is
+ * only in this callback _because it is a callback_. It should be fine
+ * to disable this callback, and the time will still get updated.
+ */
+ update_current_time(now);
+
+ /* Maybe some controller events are ready to fire */
+ control_per_second_events();
+
+ run_scheduled_events(now);
+}
+
+#ifdef HAVE_SYSTEMD_209
+static periodic_timer_t *systemd_watchdog_timer = NULL;
+
+/** Libevent callback: invoked to reset systemd watchdog. */
+static void
+systemd_watchdog_callback(periodic_timer_t *timer, void *arg)
+{
+ (void)timer;
+ (void)arg;
+ sd_notify(0, "WATCHDOG=1");
+}
+#endif /* defined(HAVE_SYSTEMD_209) */
+
+#define UPTIME_CUTOFF_FOR_NEW_BANDWIDTH_TEST (6*60*60)
+
+/** Called when our IP address seems to have changed. <b>at_interface</b>
+ * 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)
+{
+ const or_options_t *options = get_options();
+ int server = server_mode(options);
+ int exit_reject_interfaces = (server && options->ExitRelay
+ && options->ExitPolicyRejectLocalInterfaces);
+
+ if (at_interface) {
+ if (! server) {
+ /* Okay, change our keys. */
+ if (init_keys_client() < 0)
+ log_warn(LD_GENERAL, "Unable to rotate keys after IP change!");
+ }
+ } else {
+ if (server) {
+ if (get_uptime() > UPTIME_CUTOFF_FOR_NEW_BANDWIDTH_TEST)
+ reset_bandwidth_test();
+ reset_uptime();
+ router_reset_reachability();
+ }
+ }
+
+ /* Exit relays incorporate interface addresses in their exit policies when
+ * ExitPolicyRejectLocalInterfaces is set */
+ if (exit_reject_interfaces || (server && !at_interface)) {
+ 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();
+ if (periodic_events_initialized) {
+ tor_assert(check_dns_honesty_event);
+ periodic_event_reschedule(check_dns_honesty_event);
+ }
+ }
+}
+
+/** Initialize some mainloop_event_t objects that we require. */
+void
+initialize_mainloop_events(void)
+{
+ initialize_periodic_events();
+
+ if (!schedule_active_linked_connections_event) {
+ schedule_active_linked_connections_event =
+ mainloop_event_postloop_new(schedule_active_linked_connections_cb, NULL);
+ }
+ if (!postloop_cleanup_ev) {
+ postloop_cleanup_ev =
+ mainloop_event_postloop_new(postloop_cleanup_cb, NULL);
+ }
+}
+
+/** Tor main loop. */
+int
+do_main_loop(void)
+{
+ /* initialize the periodic events first, so that code that depends on the
+ * events being present does not assert.
+ */
+ initialize_periodic_events();
+ initialize_mainloop_events();
+
+ /* set up once-a-second callback. */
+ reschedule_per_second_timer();
+
+#ifdef HAVE_SYSTEMD_209
+ uint64_t watchdog_delay;
+ /* set up systemd watchdog notification. */
+ if (sd_watchdog_enabled(1, &watchdog_delay) > 0) {
+ if (! systemd_watchdog_timer) {
+ struct timeval watchdog;
+ /* The manager will "act on" us if we don't send them a notification
+ * every 'watchdog_delay' microseconds. So, send notifications twice
+ * that often. */
+ watchdog_delay /= 2;
+ watchdog.tv_sec = watchdog_delay / 1000000;
+ watchdog.tv_usec = watchdog_delay % 1000000;
+
+ systemd_watchdog_timer = periodic_timer_new(tor_libevent_get_base(),
+ &watchdog,
+ systemd_watchdog_callback,
+ NULL);
+ tor_assert(systemd_watchdog_timer);
+ }
+ }
+#endif /* defined(HAVE_SYSTEMD_209) */
+
+ main_loop_should_exit = 0;
+ main_loop_exit_value = 0;
+
+#ifdef ENABLE_RESTART_DEBUGGING
+ {
+ static int first_time = 1;
+
+ if (first_time && getenv("TOR_DEBUG_RESTART")) {
+ first_time = 0;
+ const char *sec_str = getenv("TOR_DEBUG_RESTART_AFTER_SECONDS");
+ long sec;
+ int sec_ok=0;
+ if (sec_str &&
+ (sec = tor_parse_long(sec_str, 10, 0, INT_MAX, &sec_ok, NULL)) &&
+ sec_ok) {
+ /* Okay, we parsed the seconds. */
+ } else {
+ sec = 5;
+ }
+ struct timeval restart_after = { (time_t) sec, 0 };
+ tor_shutdown_event_loop_for_restart_event =
+ tor_evtimer_new(tor_libevent_get_base(),
+ tor_shutdown_event_loop_for_restart_cb, NULL);
+ event_add(tor_shutdown_event_loop_for_restart_event, &restart_after);
+ }
+ }
+#endif
+
+ return run_main_loop_until_done();
+}
+
+#ifndef _WIN32
+/** Rate-limiter for EINVAL-type libevent warnings. */
+static ratelim_t libevent_error_ratelim = RATELIM_INIT(10);
+#endif
+
+/**
+ * Run the main loop a single time. Return 0 for "exit"; -1 for "exit with
+ * error", and 1 for "run this again."
+ */
+static int
+run_main_loop_once(void)
+{
+ int loop_result;
+
+ if (nt_service_is_stopping())
+ return 0;
+
+ if (main_loop_should_exit)
+ return 0;
+
+#ifndef _WIN32
+ /* Make it easier to tell whether libevent failure is our fault or not. */
+ errno = 0;
+#endif
+
+ if (get_options()->MainloopStats) {
+ /* We always enforce that EVLOOP_ONCE is passed to event_base_loop() if we
+ * are collecting main loop statistics. */
+ called_loop_once = 1;
+ } else {
+ called_loop_once = 0;
+ }
+
+ /* Make sure we know (about) what time it is. */
+ update_approx_time(time(NULL));
+
+ /* Here it is: the main loop. Here we tell Libevent to poll until we have
+ * an event, or the second ends, or until we have some active linked
+ * connections to trigger events for. Libevent will wait till one
+ * of these happens, then run all the appropriate callbacks. */
+ loop_result = tor_libevent_run_event_loop(tor_libevent_get_base(),
+ called_loop_once);
+
+ if (get_options()->MainloopStats) {
+ /* Update our main loop counters. */
+ if (loop_result == 0) {
+ // The call was successful.
+ increment_main_loop_success_count();
+ } else if (loop_result == -1) {
+ // The call was erroneous.
+ increment_main_loop_error_count();
+ } else if (loop_result == 1) {
+ // The call didn't have any active or pending events
+ // to handle.
+ increment_main_loop_idle_count();
+ }
+ }
+
+ /* Oh, the loop failed. That might be an error that we need to
+ * catch, but more likely, it's just an interrupted poll() call or something,
+ * and we should try again. */
+ 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_fn_ratelim(&libevent_error_ratelim, LOG_WARN, LD_NET,
+ "EINVAL from libevent: should you upgrade libevent?");
+ if (libevent_error_ratelim.n_calls_since_last_time > 8) {
+ log_err(LD_NET, "Too many libevent errors, too fast: dying");
+ return -1;
+ }
+#endif /* !defined(_WIN32) */
+ } else {
+ tor_assert_nonfatal_once(! ERRNO_IS_EINPROGRESS(e));
+ 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. */
+ return 1;
+ }
+ }
+
+ if (main_loop_should_exit)
+ return 0;
+
+ return 1;
+}
+
+/** Run the run_main_loop_once() function until it declares itself done,
+ * and return its final return value.
+ *
+ * Shadow won't invoke this function, so don't fill it up with things.
+ */
+static int
+run_main_loop_until_done(void)
+{
+ int loop_result = 1;
+ do {
+ loop_result = run_main_loop_once();
+ } while (loop_result == 1);
+
+ if (main_loop_should_exit)
+ return main_loop_exit_value;
+ else
+ return loop_result;
+}
+
+/** Returns Tor's uptime. */
+MOCK_IMPL(long,
+get_uptime,(void))
+{
+ return stats_n_seconds_working;
+}
+
+/** Reset Tor's uptime. */
+MOCK_IMPL(void,
+reset_uptime,(void))
+{
+ stats_n_seconds_working = 0;
+}
+
+void
+tor_mainloop_free_all(void)
+{
+ smartlist_free(connection_array);
+ smartlist_free(closeable_connection_lst);
+ smartlist_free(active_linked_connection_lst);
+ periodic_timer_free(second_timer);
+ teardown_periodic_events();
+ tor_event_free(shutdown_did_not_work_event);
+ tor_event_free(initialize_periodic_events_event);
+ mainloop_event_free(directory_all_unreachable_cb_event);
+ mainloop_event_free(schedule_active_linked_connections_event);
+ mainloop_event_free(postloop_cleanup_ev);
+ mainloop_event_free(handle_deferred_signewnym_ev);
+
+#ifdef HAVE_SYSTEMD_209
+ periodic_timer_free(systemd_watchdog_timer);
+#endif
+
+ stats_n_bytes_read = stats_n_bytes_written = 0;
+
+ memset(&global_bucket, 0, sizeof(global_bucket));
+ memset(&global_relayed_bucket, 0, sizeof(global_relayed_bucket));
+ time_of_process_start = 0;
+ time_of_last_signewnym = 0;
+ signewnym_is_pending = 0;
+ newnym_epoch = 0;
+ called_loop_once = 0;
+ main_loop_should_exit = 0;
+ main_loop_exit_value = 0;
+ can_complete_circuits = 0;
+ quiet_level = 0;
+ should_init_bridge_stats = 1;
+ dns_honesty_first_time = 1;
+ heartbeat_callback_first_time = 1;
+ current_second = 0;
+ memset(¤t_second_last_changed, 0,
+ sizeof(current_second_last_changed));
+}
