revert most of ef81649d2fc

Now we believe it to be the case that we never build a circuit for our
stream that has an unsuitable exit, so we'll never need to use such
a circuit. The risk is that we have some code that builds the circuit,
but now we refuse to use it, meaning we just build a bazillion circuits
and ignore them all.

src/or/circuitbuild.c

@@ -2728,7 +2728,7 @@ choose_good_exit_server_general(routerlist_t *dir, int need_uptime,
     {
       if (!ap_stream_wants_exit_attention(conn))
         continue; /* Skip everything but APs in CIRCUIT_WAIT */
-      if (connection_ap_can_use_exit(TO_EDGE_CONN(conn), router, 1)) {
+      if (connection_ap_can_use_exit(TO_EDGE_CONN(conn), router)) {
         ++n_supported[i];
 //        log_fn(LOG_DEBUG,"%s is supported. n_supported[%d] now %d.",
 //               router->nickname, i, n_supported[i]);

src/or/circuituse.c

@@ -127,7 +127,7 @@ circuit_is_acceptable(circuit_t *circ, edge_connection_t *conn,
         return 0;
       }
     }
-    if (exitrouter && !connection_ap_can_use_exit(conn, exitrouter, 0)) {
+    if (exitrouter && !connection_ap_can_use_exit(conn, exitrouter)) {
       /* can't exit from this router */
       return 0;
     }
@@ -166,6 +166,10 @@ circuit_is_better(circuit_t *a, circuit_t *b, uint8_t purpose)
           return 1;
         if (CIRCUIT_IS_ORIGIN(b) &&
             TO_ORIGIN_CIRCUIT(b)->build_state->is_internal)
+          /* XXX023 what the heck is this internal thing doing here. I
+           * think we can get rid of it. circuit_is_acceptable() already
+           * makes sure that is_internal is exactly what we need it to
+           * be. -RD */
           return 1;
       }
       break;
@@ -511,7 +515,7 @@ circuit_stream_is_being_handled(edge_connection_t *conn,
       if (exitrouter && (!need_uptime || build_state->need_uptime)) {
         int ok;
         if (conn) {
-          ok = connection_ap_can_use_exit(conn, exitrouter, 0);
+          ok = connection_ap_can_use_exit(conn, exitrouter);
         } else {
           addr_policy_result_t r = compare_addr_to_addr_policy(
               0, port, exitrouter->exit_policy);
@@ -1291,9 +1295,10 @@ circuit_get_open_circ_or_launch(edge_connection_t *conn,
        * refactor into a single function? */
       routerinfo_t *router = router_get_by_nickname(conn->chosen_exit_name, 1);
       int opt = conn->chosen_exit_optional;
-      if (router && !connection_ap_can_use_exit(conn, router, 0)) {
+      if (router && !connection_ap_can_use_exit(conn, router)) {
         log_fn(opt ? LOG_INFO : LOG_WARN, LD_APP,
-               "Requested exit point '%s' would refuse request. %s.",
+               "Requested exit point '%s' is excluded or "
+               "would refuse request. %s.",
                conn->chosen_exit_name, opt ? "Trying others" : "Closing");
         if (opt) {
           conn->chosen_exit_optional = 0;
@@ -1611,9 +1616,10 @@ connection_ap_handshake_attach_circuit(edge_connection_t *conn)
         }
         return -1;
       }
-      if (router && !connection_ap_can_use_exit(conn, router, 0)) {
+      if (router && !connection_ap_can_use_exit(conn, router)) {
         log_fn(opt ? LOG_INFO : LOG_WARN, LD_APP,
-               "Requested exit point '%s' would refuse request. %s.",
+               "Requested exit point '%s' is excluded or "
+               "would refuse request. %s.",
                conn->chosen_exit_name, opt ? "Trying others" : "Closing");
         if (opt) {
           conn->chosen_exit_optional = 0;

src/or/connection_edge.c

@@ -3044,15 +3044,9 @@ connection_edge_is_rendezvous_stream(edge_connection_t *conn)
  * to exit from it, or 0 if it probably will not allow it.
  * (We might be uncertain if conn's destination address has not yet been
  * resolved.)
- *
- * If <b>excluded_means_no</b> is 1 and Exclude*Nodes is set and excludes
- * this relay, return 0.
- * XXX022-1090 This StrictNodes business needs more work, a la bug 1090. See
- * also git commit ef81649d.
  */
 int
-connection_ap_can_use_exit(edge_connection_t *conn, routerinfo_t *exit,
-                           int excluded_means_no)
+connection_ap_can_use_exit(edge_connection_t *conn, routerinfo_t *exit)
 {
   or_options_t *options = get_options();
 
@@ -3102,17 +3096,8 @@ connection_ap_can_use_exit(edge_connection_t *conn, routerinfo_t *exit,
       return 0;
   }
   if (options->_ExcludeExitNodesUnion &&
-      (options->StrictNodes || excluded_means_no) &&
       routerset_contains_router(options->_ExcludeExitNodesUnion, exit)) {
-    /* If we are trying to avoid this node as exit, and we have StrictNodes
-     * set, then this is not a suitable exit. Refuse it.
-     *
-     * If we don't have StrictNodes set, then this function gets called in
-     * two contexts. First, we've got a circuit open and we want to know
-     * whether we can use it. In that case, we somehow built this circuit
-     * despite having the last hop in ExcludeExitNodes, so we should be
-     * willing to use it. Second, we are evaluating whether this is an
-     * acceptable exit for a new circuit. In that case, skip it. */
+    /* Not a suitable exit. Refuse it. */
     return 0;
   }
 

src/or/connection_edge.h

@@ -47,8 +47,7 @@ int connection_exit_begin_conn(cell_t *cell, circuit_t *circ);
 int connection_exit_begin_resolve(cell_t *cell, or_circuit_t *circ);
 void connection_exit_connect(edge_connection_t *conn);
 int connection_edge_is_rendezvous_stream(edge_connection_t *conn);
-int connection_ap_can_use_exit(edge_connection_t *conn, routerinfo_t *exit,
-                               int excluded_means_no);
+int connection_ap_can_use_exit(edge_connection_t *conn, routerinfo_t *exit);
 void connection_ap_expire_beginning(void);
 void connection_ap_attach_pending(void);
 void connection_ap_fail_onehop(const char *failed_digest,