Logic to implement rendezvous/introduction via unknown servers.

- Add a new extend_info_t datatype to hold information needed to
  extend a circuit (addr,port,keyid,onion_key).  Use it in cpath and
  build_state.  Make appropriate functions take or return it instead of
  routerinfo_t or keyid.

- #if 0 needless check in circuit_get_by_edge_conn; if nobody triggers this
  error in 0.1.0.10, nobody will trigger it.

- Implement new hidden service descriptor format, which contains "extend
  info" for introduction points, along with protocol version list.
  - Parse new format.
  - Generate new format
  - Cache old and new formats alongside each other.
  - Directories serve "old" format if asked in old way, "newest available"
    format if asked in new way.
  - Use new format to find introduction points if possible; otherwise fall
    back.  Keep nickname lists and extendinfo lists in sync.
  - Tests for new format.

- Implement new "v2" INTRODUCE cell format.
  - Accept new format
  - Use new format if we have a versioned service descriptor that says the
    server accepts the new format.

- Add documentation for functions and data types.


svn:r4506

1 files changed, 11 insertions, 13 deletions

diff --git a/src/or/relay.c b/src/or/relay.c
index dd424be107..ff77955110 100644
--- a/src/or/relay.c
+++ b/src/or/relay.c
@@ -633,11 +633,8 @@ connection_edge_process_end_not_open(
     log_fn(LOG_INFO,"Address '%s' refused due to '%s'. Considering retrying.",
            safe_str(conn->socks_request->address),
            connection_edge_end_reason_str(reason));
-    exitrouter = router_get_by_digest(circ->build_state->chosen_exit_digest);
-    if (!exitrouter) {
-      log_fn(LOG_INFO,"Skipping broken circ (exit router vanished)");
-      return 0; /* this circuit is screwed and doesn't know it yet */
-    }
+    exitrouter =
+      router_get_by_digest(circ->build_state->chosen_exit->identity_digest);
     switch (reason) {
       case END_STREAM_REASON_EXITPOLICY:
         if (rh->length >= 5) {
@@ -652,15 +649,15 @@ connection_edge_process_end_not_open(
                                     conn->chosen_exit_name);
         }
         /* check if he *ought* to have allowed it */
-        if (rh->length < 5 ||
-            (!tor_inet_aton(conn->socks_request->address, &in) &&
-             !conn->chosen_exit_name)) {
+        if (exitrouter &&
+            (rh->length < 5 ||
+             (!tor_inet_aton(conn->socks_request->address, &in) &&
+              !conn->chosen_exit_name))) {
           log_fn(LOG_NOTICE,"Exitrouter '%s' seems to be more restrictive than its exit policy. Not using this router as exit for now.", exitrouter->nickname);
           addr_policy_free(exitrouter->exit_policy);
           exitrouter->exit_policy =
             router_parse_addr_policy_from_string("reject *:*");
         }
-
         if (connection_ap_detach_retriable(conn, circ) >= 0)
           return 0;
         /* else, conn will get closed below */
@@ -683,10 +680,11 @@ connection_edge_process_end_not_open(
         break;
       case END_STREAM_REASON_HIBERNATING:
       case END_STREAM_REASON_RESOURCELIMIT:
-        addr_policy_free(exitrouter->exit_policy);
-        exitrouter->exit_policy =
-          router_parse_addr_policy_from_string("reject *:*");
-
+        if (exitrouter) {
+          addr_policy_free(exitrouter->exit_policy);
+          exitrouter->exit_policy =
+            router_parse_addr_policy_from_string("reject *:*");
+        }
         if (connection_ap_detach_retriable(conn, circ) >= 0)
           return 0;
         /* else, will close below */