Merge remote-tracking branch 'arma/feature13153'

changes/feature13153

@@ -0,0 +1,5 @@
+  o Code simplication:
+    - Clients are now willing to send optimistic circuit data (before they
+      receive a 'connected' cell) to relays of any version. We used to
+      only do it for relays running 0.2.3.1-alpha or later, but now all
+      relays are new enough. Resolves ticket 13153.

src/or/circuituse.c

@@ -2070,7 +2070,7 @@ static void
 link_apconn_to_circ(entry_connection_t *apconn, origin_circuit_t *circ,
                     crypt_path_t *cpath)
 {
-  const node_t *exitnode;
+  const node_t *exitnode = NULL;
 
   /* add it into the linked list of streams on this circuit */
   log_debug(LD_APP|LD_CIRC, "attaching new conn to circ. n_circ_id %u.",
@@ -2104,23 +2104,22 @@ link_apconn_to_circ(entry_connection_t *apconn, origin_circuit_t *circ,
   circ->isolation_any_streams_attached = 1;
   connection_edge_update_circuit_isolation(apconn, circ, 0);
 
+  /* Compute the exitnode if possible, for logging below */
+  if (cpath->extend_info)
+    exitnode = node_get_by_id(cpath->extend_info->identity_digest);
+
   /* See if we can use optimistic data on this circuit */
-  if (cpath->extend_info &&
-      (exitnode = node_get_by_id(cpath->extend_info->identity_digest)) &&
-      exitnode->rs) {
-    /* Okay; we know what exit node this is. */
-    if (optimistic_data_enabled() &&
-        circ->base_.purpose == CIRCUIT_PURPOSE_C_GENERAL &&
-        exitnode->rs->version_supports_optimistic_data)
-      apconn->may_use_optimistic_data = 1;
-    else
-      apconn->may_use_optimistic_data = 0;
-    log_info(LD_APP, "Looks like completed circuit to %s %s allow "
-             "optimistic data for connection to %s",
-             safe_str_client(node_describe(exitnode)),
-             apconn->may_use_optimistic_data ? "does" : "doesn't",
-             safe_str_client(apconn->socks_request->address));
-  }
+  if (optimistic_data_enabled() &&
+      circ->base_.purpose == CIRCUIT_PURPOSE_C_GENERAL)
+    apconn->may_use_optimistic_data = 1;
+  else
+    apconn->may_use_optimistic_data = 0;
+  log_info(LD_APP, "Looks like completed circuit to %s %s allow "
+           "optimistic data for connection to %s",
+           /* node_describe() does the right thing if exitnode is NULL */
+           safe_str_client(node_describe(exitnode)),
+           apconn->may_use_optimistic_data ? "does" : "doesn't",
+           safe_str_client(apconn->socks_request->address));
 }
 
 /** Return true iff <b>address</b> is matched by one of the entries in

src/or/or.h

@@ -2149,9 +2149,6 @@ typedef struct routerstatus_t {
   /** True iff this router is a version that, if it caches directory info,
    * we can get microdescriptors from. */
   unsigned int version_supports_microdesc_cache:1;
-  /** True iff this router is a version that allows DATA cells to arrive on
-   * a stream before it has sent a CONNECTED cell. */
-  unsigned int version_supports_optimistic_data:1;
   /** True iff this router has a version that allows it to accept EXTEND2
    * cells */
   unsigned int version_supports_extend2_cells:1;

src/or/routerparse.c

@@ -1916,12 +1916,9 @@ routerstatus_parse_entry_from_string(memarea_t *area,
     rs->version_known = 1;
     if (strcmpstart(tok->args[0], "Tor ")) {
       rs->version_supports_microdesc_cache = 1;
-      rs->version_supports_optimistic_data = 1;
     } else {
       rs->version_supports_microdesc_cache =
         tor_version_supports_microdescriptors(tok->args[0]);
-      rs->version_supports_optimistic_data =
-        tor_version_as_new_as(tok->args[0], "0.2.3.1-alpha");
       rs->version_supports_extend2_cells =
         tor_version_as_new_as(tok->args[0], "0.2.4.8-alpha");
     }