dos: Add a heartbeat log

Signed-off-by: David Goulet <dgoulet@torproject.org>

src/or/dos.c

@@ -555,6 +555,51 @@ dos_should_refuse_single_hop_client(void)
                                        0 /* default */, 0, 1);
 }
 
+/* Log a heartbeat message with some statistics. */
+void
+dos_log_heartbeat(void)
+{
+  char *conn_msg = NULL;
+  char *cc_msg = NULL;
+  char *single_hop_client_msg = NULL;
+
+  if (!dos_is_enabled()) {
+    goto end;
+  }
+
+  if (dos_cc_enabled) {
+    tor_asprintf(&cc_msg,
+                 " %" PRIu64 " circuits rejected,"
+                 " %" PRIu32 " marked addresses.",
+                 cc_num_rejected_cells, cc_num_marked_addrs);
+  }
+
+  if (dos_conn_enabled) {
+    tor_asprintf(&conn_msg,
+                 " %" PRIu64 " connections closed.",
+                 conn_num_addr_rejected);
+  }
+
+  if (dos_should_refuse_single_hop_client()) {
+    tor_asprintf(&single_hop_client_msg,
+                 " %" PRIu64 " single hop clients refused.",
+                 num_single_hop_client_refused);
+  }
+
+  log_notice(LD_HEARTBEAT,
+             "DoS mitigation since startup:%s%s%s",
+             (cc_msg != NULL) ? cc_msg : " [cc not enabled]",
+             (conn_msg != NULL) ? conn_msg : " [conn not enabled]",
+             (single_hop_client_msg != NULL) ? single_hop_client_msg : "");
+
+  tor_free(conn_msg);
+  tor_free(cc_msg);
+  tor_free(single_hop_client_msg);
+
+ end:
+  return;
+}
+
 /* Called when a new client connection has been established on the given
  * address. */
 void

src/or/dos.h

@@ -47,6 +47,7 @@ void dos_init(void);
 void dos_free_all(void);
 void dos_consensus_has_changed(const networkstatus_t *ns);
 int dos_enabled(void);
+void dos_log_heartbeat(void);
 
 void dos_new_client_conn(or_connection_t *or_conn);
 void dos_close_client_conn(const or_connection_t *or_conn);

src/or/status.c

@@ -27,6 +27,7 @@
 #include "hibernate.h"
 #include "rephist.h"
 #include "statefile.h"
+#include "dos.h"
 
 static void log_accounting(const time_t now, const or_options_t *options);
 #include "geoip.h"
@@ -145,6 +146,7 @@ log_heartbeat(time_t now)
   if (public_server_mode(options)) {
     rep_hist_log_circuit_handshake_stats(now);
     rep_hist_log_link_protocol_counts();
+    dos_log_heartbeat();
   }
 
   circuit_log_ancient_one_hop_circuits(1800);