1 files changed, 15 insertions, 0 deletions
diff --git a/src/or/circuitbuild.c b/src/or/circuitbuild.c
index baa7bad2e6..a15f4c28b5 100644
--- a/src/or/circuitbuild.c
+++ b/src/or/circuitbuild.c
@@ -2419,3 +2419,18 @@ build_state_get_exit_nickname(cpath_build_state_t *state)
   return state->chosen_exit->nickname;
 }
 
+/** Return true iff the given address can be used to extend to. */
+int extend_info_addr_is_allowed(const tor_addr_t *addr)
+{
+  tor_assert(addr);
+
+  /* Check if we have a private address and if we can extend to it. */
+  if ((tor_addr_is_internal(addr, 0) || tor_addr_is_multicast(addr)) &&
+      !get_options()->ExtendAllowPrivateAddresses) {
+    goto disallow;
+  }
+  /* Allowed! */
+  return 1;
+ disallow:
+  return 0;
+}