Merge remote-tracking branch 'rransom-tor/bug3309' into maint-0.2.2

5 files changed, 63 insertions, 6 deletions

diff --git a/changes/bug3309 b/changes/bug3309
new file mode 100644
index 000000000..104056d8e
--- /dev/null
+++ b/changes/bug3309
@@ -0,0 +1,13 @@
+  o Minor bugfixes:
+    - Clear the table recording the time of the last request for each
+      hidden service descriptor from each HS directory on SIGNAL
+      NEWNYM.  Previously, we would clear our HS descriptor cache on
+      SIGNAL NEWNYM, but if we had previously retrieved a descriptor
+      (or tried to) from every directory responsible for it, we would
+      refuse to fetch it again for up to 15 minutes.  Bugfix on
+      0.2.2.25-alpha; fixes bug 3309.
+
+  o Minor features:
+    - Log (at info level) when purging pieces of hidden-service-client
+      state on SIGNAL NEWNYM.
+
diff --git a/src/or/main.c b/src/or/main.c
index adbde9044..bc639dbdd 100644
--- a/src/or/main.c
+++ b/src/or/main.c
@@ -853,8 +853,7 @@ signewnym_impl(time_t now)
 
   circuit_expire_all_dirty_circs();
   addressmap_clear_transient();
-  rend_cache_purge();
-  rend_client_cancel_descriptor_fetches();
+  rend_client_purge_state();
   time_of_last_signewnym = now;
   signewnym_is_pending = 0;
 }
diff --git a/src/or/rendclient.c b/src/or/rendclient.c
index 29b9d260e..533dfb8a9 100644
--- a/src/or/rendclient.c
+++ b/src/or/rendclient.c
@@ -27,6 +27,16 @@ static extend_info_t *rend_client_get_random_intro_impl(
                           const rend_cache_entry_t *rend_query,
                           const int strict, const int warnings);
 
+/** Purge all potentially remotely-detectable state held in the hidden
+ * service client code.  Called on SIGNAL NEWNYM. */
+void
+rend_client_purge_state(void)
+{
+  rend_cache_purge();
+  rend_client_cancel_descriptor_fetches();
+  rend_client_purge_last_hid_serv_requests();
+}
+
 /** Called when we've established a circuit to an introduction point:
  * send the introduction request. */
 void
@@ -377,7 +387,17 @@ rend_client_introduction_acked(origin_circuit_t *circ,
  * certain queries; keys are strings consisting of base32-encoded
  * hidden service directory identities and base32-encoded descriptor IDs;
  * values are pointers to timestamps of the last requests. */
-static strmap_t *last_hid_serv_requests = NULL;
+static strmap_t *last_hid_serv_requests_ = NULL;
+
+/** Returns last_hid_serv_requests_, initializing it to a new strmap if
+ * necessary. */
+static strmap_t *
+get_last_hid_serv_requests(void)
+{
+  if (!last_hid_serv_requests_)
+    last_hid_serv_requests_ = strmap_new();
+  return last_hid_serv_requests_;
+}
 
 /** Look up the last request time to hidden service directory <b>hs_dir</b>
  * for descriptor ID <b>desc_id_base32</b>. If <b>set</b> is non-zero,
@@ -391,6 +411,7 @@ lookup_last_hid_serv_request(routerstatus_t *hs_dir,
   char hsdir_id_base32[REND_DESC_ID_V2_LEN_BASE32 + 1];
   char hsdir_desc_comb_id[2 * REND_DESC_ID_V2_LEN_BASE32 + 1];
   time_t *last_request_ptr;
+  strmap_t *last_hid_serv_requests = get_last_hid_serv_requests();
   base32_encode(hsdir_id_base32, sizeof(hsdir_id_base32),
                 hs_dir->identity_digest, DIGEST_LEN);
   tor_snprintf(hsdir_desc_comb_id, sizeof(hsdir_desc_comb_id), "%s%s",
@@ -416,8 +437,7 @@ directory_clean_last_hid_serv_requests(void)
 {
   strmap_iter_t *iter;
   time_t cutoff = time(NULL) - REND_HID_SERV_DIR_REQUERY_PERIOD;
-  if (!last_hid_serv_requests)
-    last_hid_serv_requests = strmap_new();
+  strmap_t *last_hid_serv_requests = get_last_hid_serv_requests();
   for (iter = strmap_iter_init(last_hid_serv_requests);
        !strmap_iter_done(iter); ) {
     const char *key;
@@ -434,6 +454,26 @@ directory_clean_last_hid_serv_requests(void)
   }
 }
 
+/** Purge the history of request times to hidden service directories,
+ * so that future lookups of an HS descriptor will not fail because we
+ * accessed all of the HSDir relays responsible for the descriptor
+ * recently. */
+void
+rend_client_purge_last_hid_serv_requests(void)
+{
+  /* Don't create the table if it doesn't exist yet (and it may very
+   * well not exist if the user hasn't accessed any HSes)... */
+  strmap_t *old_last_hid_serv_requests = last_hid_serv_requests_;
+  /* ... and let get_last_hid_serv_requests re-create it for us if
+   * necessary. */
+  last_hid_serv_requests_ = NULL;
+
+  if (old_last_hid_serv_requests != NULL) {
+    log_info(LD_REND, "Purging client last-HS-desc-request-time table");
+    strmap_free(old_last_hid_serv_requests, _tor_free);
+  }
+}
+
 /** Determine the responsible hidden service directories for <b>desc_id</b>
  * and fetch the descriptor belonging to that ID from one of them. Only
  * send a request to hidden service directories that we did not try within
diff --git a/src/or/rendclient.h b/src/or/rendclient.h
index 6910c1a97..c6cf82b3d 100644
--- a/src/or/rendclient.h
+++ b/src/or/rendclient.h
@@ -12,6 +12,8 @@
 #ifndef _TOR_RENDCLIENT_H
 #define _TOR_RENDCLIENT_H
 
+void rend_client_purge_state(void);
+
 void rend_client_introcirc_has_opened(origin_circuit_t *circ);
 void rend_client_rendcirc_has_opened(origin_circuit_t *circ);
 int rend_client_introduction_acked(origin_circuit_t *circ,
@@ -19,6 +21,7 @@ int rend_client_introduction_acked(origin_circuit_t *circ,
                                    size_t request_len);
 void rend_client_refetch_v2_renddesc(const rend_data_t *rend_query);
 void rend_client_cancel_descriptor_fetches(void);
+void rend_client_purge_last_hid_serv_requests(void);
 int rend_client_remove_intro_point(extend_info_t *failed_intro,
                                    const rend_data_t *rend_query);
 int rend_client_rendezvous_acked(origin_circuit_t *circ,
diff --git a/src/or/rendcommon.c b/src/or/rendcommon.c
index 4d4a90f61..683e11ad2 100644
--- a/src/or/rendcommon.c
+++ b/src/or/rendcommon.c
@@ -839,8 +839,10 @@ rend_cache_clean(void)
 void
 rend_cache_purge(void)
 {
-  if (rend_cache)
+  if (rend_cache) {
+    log_info(LD_REND, "Purging client/v0-HS-authority HS descriptor cache");
     strmap_free(rend_cache, _rend_cache_entry_free);
+  }
   rend_cache = strmap_new();
 }