[or-cvs] [tor/master] immediate reachability check for new relays

[arma at torproject.org]

Author: Roger Dingledine <arma at torproject.org>
Date: Wed, 21 Apr 2010 03:12:14 -0400
Subject: immediate reachability check for new relays
Commit: 4f307e038272e368cd307ffa5e31b568b0729c48

---
 changes/immediate_reachability_check |    7 +++++++
 src/or/dirserv.c                     |   26 ++++++++++++++++++--------
 src/or/dirvote.c                     |    3 ++-
 src/or/or.h                          |    1 +
 src/or/routerlist.c                  |   10 ++++++++--
 5 files changed, 36 insertions(+), 11 deletions(-)
 create mode 100644 changes/immediate_reachability_check

diff --git a/changes/immediate_reachability_check b/changes/immediate_reachability_check
new file mode 100644
index 0000000..0352356
--- /dev/null
+++ b/changes/immediate_reachability_check
@@ -0,0 +1,7 @@
+  o Minor features:
+    - Directory authorities now do an immediate reachability check as soon
+      as they hear about a new relay. This change should slightly reduce
+      the time between setting up a relay and getting listed as running
+      in the consensus. It should also improve the time between setting
+      up a bridge and seeing use by bridge users.
+
diff --git a/src/or/dirserv.c b/src/or/dirserv.c
index b5c4c7b..ad96e76 100644
--- a/src/or/dirserv.c
+++ b/src/or/dirserv.c
@@ -3091,6 +3091,23 @@ dirserv_orconn_tls_done(const char *address,
    * skip testing. */
 }
 
+/** Helper function for dirserv_test_reachability(). Start a TLS
+ * connection to <b>router</b>, and annotate it with when we started
+ * the test. */
+void
+dirserv_single_reachability_test(time_t now, routerinfo_t *router)
+{
+  tor_addr_t router_addr;
+  log_debug(LD_OR,"Testing reachability of %s at %s:%u.",
+            router->nickname, router->address, router->or_port);
+  /* Remember when we started trying to determine reachability */
+  if (!router->testing_since)
+    router->testing_since = now;
+  tor_addr_from_ipv4h(&router_addr, router->addr);
+  connection_or_connect(&router_addr, router->or_port,
+                        router->cache_info.identity_digest);
+}
+
 /** Auth dir server only: if <b>try_all</b> is 1, launch connections to
  * all known routers; else we want to load balance such that we only
  * try a few connections per call.
@@ -3117,7 +3134,6 @@ dirserv_test_reachability(time_t now, int try_all)
 
   SMARTLIST_FOREACH_BEGIN(rl->routers, routerinfo_t *, router) {
     const char *id_digest = router->cache_info.identity_digest;
-    tor_addr_t router_addr;
     if (router_is_me(router))
       continue;
     if (bridge_auth && router->purpose != ROUTER_PURPOSE_BRIDGE)
@@ -3125,13 +3141,7 @@ dirserv_test_reachability(time_t now, int try_all)
 //    if (router->cache_info.published_on > cutoff)
 //      continue;
     if (try_all || (((uint8_t)id_digest[0]) % 128) == ctr) {
-      log_debug(LD_OR,"Testing reachability of %s at %s:%u.",
-                router->nickname, router->address, router->or_port);
-      /* Remember when we started trying to determine reachability */
-      if (!router->testing_since)
-        router->testing_since = now;
-      tor_addr_from_ipv4h(&router_addr, router->addr);
-      connection_or_connect(&router_addr, router->or_port, id_digest);
+      dirserv_single_reachability_test(now, router);
     }
   } SMARTLIST_FOREACH_END(router);
   if (!try_all) /* increment ctr */
diff --git a/src/or/dirvote.c b/src/or/dirvote.c
index 6053e50..d561013 100644
--- a/src/or/dirvote.c
+++ b/src/or/dirvote.c
@@ -2696,7 +2696,8 @@ dirvote_add_vote(const char *vote_body, const char **msg_out, int *status_out)
         networkstatus_voter_info_t *vi_old = get_voter(v->vote);
         if (!memcmp(vi_old->vote_digest, vi->vote_digest, DIGEST_LEN)) {
           /* Ah, it's the same vote. Not a problem. */
-          log_info(LD_DIR, "Discarding a vote we already have.");
+          log_info(LD_DIR, "Discarding a vote we already have (from %s).",
+                   vi->address);
           if (*status_out < 200)
             *status_out = 200;
           goto discard;
diff --git a/src/or/or.h b/src/or/or.h
index e365f69..71a9ff7 100644
--- a/src/or/or.h
+++ b/src/or/or.h
@@ -3913,6 +3913,7 @@ void dirserv_orconn_tls_done(const char *address,
                              uint16_t or_port,
                              const char *digest_rcvd,
                              int as_advertised);
+void dirserv_single_reachability_test(time_t now, routerinfo_t *router);
 void dirserv_test_reachability(time_t now, int try_all);
 int authdir_wants_to_reject_router(routerinfo_t *ri, const char **msg,
                                    int complain);
diff --git a/src/or/routerlist.c b/src/or/routerlist.c
index 637163a..f4db40d 100644
--- a/src/or/routerlist.c
+++ b/src/or/routerlist.c
@@ -3204,7 +3204,7 @@ router_add_to_routerlist(routerinfo_t *router, const char **msg,
     if (!in_consensus && (router->cache_info.published_on <=
                           old_router->cache_info.published_on)) {
       /* Same key, but old.  This one is not listed in the consensus. */
-      log_debug(LD_DIR, "Skipping not-new descriptor for router '%s'",
+      log_debug(LD_DIR, "Not-new descriptor for router '%s'",
                 router->nickname);
       /* Only journal this desc if we'll be serving it. */
       if (!from_cache && should_cache_old_descriptors())
@@ -3247,9 +3247,15 @@ router_add_to_routerlist(routerinfo_t *router, const char **msg,
   /* We haven't seen a router with this identity before. Add it to the end of
    * the list. */
   routerlist_insert(routerlist, router);
-  if (!from_cache)
+  if (!from_cache) {
+    if (authdir) {
+      /* launch an immediate reachability test, so we will have an opinion
+       * soon in case we're generating a consensus soon */
+      dirserv_single_reachability_test(time(NULL), router);
+    }
     signed_desc_append_to_journal(&router->cache_info,
                                   &routerlist->desc_store);
+  }
   directory_set_dirty();
   return ROUTER_ADDED_SUCCESSFULLY;
 }
-- 
1.6.5