Merge branch 'maint-0.2.9' into release-0.2.9

changes/bug31107

@@ -0,0 +1,4 @@
+  o Minor bugfixes (logging, protocol violations):
+    - Do not log a nonfatal assertion failure when receiving a VERSIONS
+      cell on a connection using the obsolete v1 link protocol. Log a
+      protocol_warn instead. Fixes bug 31107; bugfix on 0.2.4.4-alpha.

changes/ticket31466

@@ -0,0 +1,5 @@
+  o Minor bugfixes (logging):
+    - Rate-limit our the logging message about the obsolete .exit notation.
+      Previously, there was no limit on this warning, which could potentially
+      be triggered many times by a hostile website. Fixes bug 31466;
+      bugfix on 0.2.2.1-alpha.

src/or/channeltls.c

@@ -1098,7 +1098,15 @@ channel_tls_handle_cell(cell_t *cell, or_connection_t *conn)
       /* do nothing */
       break;
     case CELL_VERSIONS:
-      tor_fragile_assert();
+      /* A VERSIONS cell should always be a variable-length cell, and
+       * so should never reach this function (which handles constant-sized
+       * cells). But if the connection is using the (obsolete) v1 link
+       * protocol, all cells will be treated as constant-sized, and so
+       * it's possible we'll reach this code.
+       */
+      log_fn(LOG_PROTOCOL_WARN, LD_CHANNEL,
+             "Received unexpected VERSIONS cell on a channel using link "
+             "protocol %d; ignoring.", conn->link_proto);
       break;
     case CELL_NETINFO:
       ++stats_n_netinfo_cells_processed;

src/or/connection_edge.c

@@ -1186,9 +1186,11 @@ connection_ap_handshake_rewrite(entry_connection_t *conn,
    * disallowed when they're coming straight from the client, but you're
    * allowed to have them in MapAddress commands and so forth. */
   if (!strcmpend(socks->address, ".exit") && !options->AllowDotExit) {
-    log_warn(LD_APP, "The  \".exit\" notation is disabled in Tor due to "
-             "security risks. Set AllowDotExit in your torrc to enable "
-             "it (at your own risk).");
+    static ratelim_t exit_warning_limit = RATELIM_INIT(60*15);
+    log_fn_ratelim(&exit_warning_limit, LOG_WARN, LD_APP,
+                   "The  \".exit\" notation is disabled in Tor due to "
+                   "security risks.  Set AllowDotExit in your torrc to enable "
+                   "it (at your own risk).");
     control_event_client_status(LOG_WARN, "SOCKS_BAD_HOSTNAME HOSTNAME=%s",
                                 escaped(socks->address));
     out->end_reason = END_STREAM_REASON_TORPROTOCOL;