1 files changed, 51 insertions, 52 deletions

diff --git a/src/core/mainloop/connection.c b/src/core/mainloop/connection.c
index c827af7a9a..b17d7bf2bd 100644
--- a/src/core/mainloop/connection.c
+++ b/src/core/mainloop/connection.c
@@ -1,7 +1,7 @@
 /* Copyright (c) 2001 Matej Pfajfar.
  * Copyright (c) 2001-2004, Roger Dingledine.
  * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
- * Copyright (c) 2007-2020, The Tor Project, Inc. */
+ * Copyright (c) 2007-2021, The Tor Project, Inc. */
 /* See LICENSE for licensing information */
 
 /**
@@ -106,7 +106,6 @@
 #include "feature/relay/dns.h"
 #include "feature/relay/ext_orport.h"
 #include "feature/relay/routermode.h"
-#include "feature/rend/rendclient.h"
 #include "feature/rend/rendcommon.h"
 #include "feature/stats/connstats.h"
 #include "feature/stats/rephist.h"
@@ -898,7 +897,6 @@ connection_free_minimal(connection_t *conn)
     }
   }
   if (CONN_IS_EDGE(conn)) {
-    rend_data_free(TO_EDGE_CONN(conn)->rend_data);
     hs_ident_edge_conn_free(TO_EDGE_CONN(conn)->hs_ident);
   }
   if (conn->type == CONN_TYPE_CONTROL) {
@@ -927,7 +925,6 @@ connection_free_minimal(connection_t *conn)
     tor_compress_free(dir_conn->compress_state);
     dir_conn_clear_spool(dir_conn);
 
-    rend_data_free(dir_conn->rend_data);
     hs_ident_dir_conn_free(dir_conn->hs_ident);
     if (dir_conn->guard_state) {
       /* Cancel before freeing, if it's still there. */
@@ -948,7 +945,6 @@ connection_free_minimal(connection_t *conn)
     connection_or_clear_identity(TO_OR_CONN(conn));
   }
   if (conn->type == CONN_TYPE_OR || conn->type == CONN_TYPE_EXT_OR) {
-    connection_or_remove_from_ext_or_id_map(TO_OR_CONN(conn));
     tor_free(TO_OR_CONN(conn)->ext_or_conn_id);
     tor_free(TO_OR_CONN(conn)->ext_or_auth_correct_client_hash);
     tor_free(TO_OR_CONN(conn)->ext_or_transport);
@@ -1243,12 +1239,34 @@ create_unix_sockaddr(const char *listenaddress, char **readable_address,
 }
 #endif /* defined(HAVE_SYS_UN_H) || defined(RUNNING_DOXYGEN) */
 
-/** Warn that an accept or a connect has failed because we're running out of
- * TCP sockets we can use on current system.  Rate-limit these warnings so
- * that we don't spam the log. */
+/**
+ * A socket failed from resource exhaustion.
+ *
+ * Among other actions, warn that an accept or a connect has failed because
+ * we're running out of TCP sockets we can use on current system.  Rate-limit
+ * these warnings so that we don't spam the log. */
 static void
-warn_too_many_conns(void)
+socket_failed_from_resource_exhaustion(void)
 {
+  /* When we get to this point we know that a socket could not be
+   * established. However the kernel does not let us know whether the reason is
+   * because we ran out of TCP source ports, or because we exhausted all the
+   * FDs on this system, or for any other reason.
+   *
+   * For this reason, we are going to use the following heuristic: If our
+   * system supports a lot of sockets, we will assume that it's a problem of
+   * TCP port exhaustion. Otherwise, if our system does not support many
+   * sockets, we will assume that this is because of file descriptor
+   * exhaustion.
+   */
+  if (get_max_sockets() > 65535) {
+    /* TCP port exhaustion */
+    rep_hist_note_overload(OVERLOAD_GENERAL);
+  } else {
+    /* File descriptor exhaustion */
+    rep_hist_note_overload(OVERLOAD_FD_EXHAUSTED);
+  }
+
 #define WARN_TOO_MANY_CONNS_INTERVAL (6*60*60)
   static ratelim_t last_warned = RATELIM_INIT(WARN_TOO_MANY_CONNS_INTERVAL);
   char *m;
@@ -1477,7 +1495,7 @@ connection_listener_new(const struct sockaddr *listensockaddr,
     if (!SOCKET_OK(s)) {
       int e = tor_socket_errno(s);
       if (ERRNO_IS_RESOURCE_LIMIT(e)) {
-        warn_too_many_conns();
+        socket_failed_from_resource_exhaustion();
         /*
          * We'll call the OOS handler at the error exit, so set the
          * exhaustion flag for it.
@@ -1603,7 +1621,7 @@ connection_listener_new(const struct sockaddr *listensockaddr,
     if (! SOCKET_OK(s)) {
       int e = tor_socket_errno(s);
       if (ERRNO_IS_RESOURCE_LIMIT(e)) {
-        warn_too_many_conns();
+        socket_failed_from_resource_exhaustion();
         /*
          * We'll call the OOS handler at the error exit, so set the
          * exhaustion flag for it.
@@ -1718,13 +1736,6 @@ connection_listener_new(const struct sockaddr *listensockaddr,
     }
   }
 
-  /* Force IPv4 and IPv6 traffic on for non-SOCKSPorts.
-   * Forcing options on isn't a good idea, see #32994 and #33607. */
-  if (type != CONN_TYPE_AP_LISTENER) {
-    lis_conn->entry_cfg.ipv4_traffic = 1;
-    lis_conn->entry_cfg.ipv6_traffic = 1;
-  }
-
   if (connection_add(conn) < 0) { /* no space, forget it */
     log_warn(LD_NET,"connection_add for listener failed. Giving up.");
     goto err;
@@ -1923,7 +1934,7 @@ connection_handle_listener_read(connection_t *conn, int new_type)
       connection_check_oos(get_n_open_sockets(), 0);
       return 0;
     } else if (ERRNO_IS_RESOURCE_LIMIT(e)) {
-      warn_too_many_conns();
+      socket_failed_from_resource_exhaustion();
       /* Exhaustion; tell the OOS handler */
       connection_check_oos(get_n_open_sockets(), 1);
       return 0;
@@ -2186,7 +2197,7 @@ connection_connect_sockaddr,(connection_t *conn,
      */
     *socket_error = tor_socket_errno(s);
     if (ERRNO_IS_RESOURCE_LIMIT(*socket_error)) {
-      warn_too_many_conns();
+      socket_failed_from_resource_exhaustion();
       connection_check_oos(get_n_open_sockets(), 1);
     } else {
       log_warn(LD_NET,"Error creating network socket: %s",
@@ -3246,7 +3257,7 @@ retry_all_listeners(smartlist_t *new_conns, int close_all_noncontrol)
      * we hit those, bail early so tor can stop. */
     if (!new_conn) {
       log_warn(LD_NET, "Unable to create listener port: %s:%d",
-               fmt_addr(&r->new_port->addr), r->new_port->port);
+               fmt_and_decorate_addr(&r->new_port->addr), r->new_port->port);
       retval = -1;
       break;
     }
@@ -3265,7 +3276,8 @@ retry_all_listeners(smartlist_t *new_conns, int close_all_noncontrol)
    * any configured port.  Kill 'em. */
   SMARTLIST_FOREACH_BEGIN(listeners, connection_t *, conn) {
     log_notice(LD_NET, "Closing no-longer-configured %s on %s:%d",
-               conn_type_to_string(conn->type), conn->address, conn->port);
+               conn_type_to_string(conn->type),
+               fmt_and_decorate_addr(&conn->addr), conn->port);
     connection_close_immediate(conn);
     connection_mark_for_close(conn);
   } SMARTLIST_FOREACH_END(conn);
@@ -3427,6 +3439,16 @@ connection_bucket_read_limit(connection_t *conn, time_t now)
   int priority = conn->type != CONN_TYPE_DIR;
   ssize_t conn_bucket = -1;
   size_t global_bucket_val = token_bucket_rw_get_read(&global_bucket);
+  if (global_bucket_val == 0) {
+    /* We reached our global read limit: count this as an overload.
+     *
+     * The token bucket is always initialized (see connection_bucket_init() and
+     * options_validate_relay_bandwidth()) and hence we can assume that if the
+     * token ever hits zero, it's a limit that got popped and not the bucket
+     * being uninitialized.
+     */
+    rep_hist_note_overload(OVERLOAD_READ);
+  }
 
   if (connection_speaks_cells(conn)) {
     or_connection_t *or_conn = TO_OR_CONN(conn);
@@ -3457,6 +3479,11 @@ connection_bucket_write_limit(connection_t *conn, time_t now)
   int priority = conn->type != CONN_TYPE_DIR;
   size_t conn_bucket = buf_datalen(conn->outbuf);
   size_t global_bucket_val = token_bucket_rw_get_write(&global_bucket);
+  if (global_bucket_val == 0) {
+    /* We reached our global write limit: We should count this as an overload.
+     * See above function for more information */
+    rep_hist_note_overload(OVERLOAD_WRITE);
+  }
 
   if (!connection_is_rate_limited(conn)) {
     /* be willing to write to local conns even if our buckets are empty */
@@ -4812,34 +4839,6 @@ connection_get_by_type_nonlinked,(int type))
   CONN_GET_TEMPLATE(conn, conn->type == type && !conn->linked);
 }
 
-/** Return a connection of type <b>type</b> that has rendquery equal
- * to <b>rendquery</b>, and that is not marked for close. If state
- * is non-zero, conn must be of that state too.
- */
-connection_t *
-connection_get_by_type_state_rendquery(int type, int state,
-                                       const char *rendquery)
-{
-  tor_assert(type == CONN_TYPE_DIR ||
-             type == CONN_TYPE_AP || type == CONN_TYPE_EXIT);
-  tor_assert(rendquery);
-
-  CONN_GET_TEMPLATE(conn,
-       (conn->type == type &&
-        (!state || state == conn->state)) &&
-        (
-         (type == CONN_TYPE_DIR &&
-          TO_DIR_CONN(conn)->rend_data &&
-          !rend_cmp_service_ids(rendquery,
-                    rend_data_get_address(TO_DIR_CONN(conn)->rend_data)))
-         ||
-              (CONN_IS_EDGE(conn) &&
-               TO_EDGE_CONN(conn)->rend_data &&
-               !rend_cmp_service_ids(rendquery,
-                    rend_data_get_address(TO_EDGE_CONN(conn)->rend_data)))
-         ));
-}
-
 /** Return a new smartlist of dir_connection_t * from get_connection_array()
  * that satisfy conn_test on connection_t *conn_var, and dirconn_test on
  * dir_connection_t *dirconn_var. conn_var must be of CONN_TYPE_DIR and not
@@ -5829,7 +5828,6 @@ connection_free_all(void)
 
   /* Unlink everything from the identity map. */
   connection_or_clear_identity_map();
-  connection_or_clear_ext_or_id_map();
 
   /* Clear out our list of broken connections */
   clear_broken_connection_map(0);
@@ -5866,7 +5864,8 @@ clock_skew_warning, (const connection_t *conn, long apparent_skew, int trusted,
   char *ext_source = NULL, *warn = NULL;
   format_time_interval(dbuf, sizeof(dbuf), apparent_skew);
   if (conn)
-    tor_asprintf(&ext_source, "%s:%s:%d", source, conn->address, conn->port);
+    tor_asprintf(&ext_source, "%s:%s:%d", source,
+                 fmt_and_decorate_addr(&conn->addr), conn->port);
   else
     ext_source = tor_strdup(source);
   log_fn(trusted ? LOG_WARN : LOG_INFO, domain,