4 files changed, 26 insertions, 0 deletions
diff --git a/src/feature/control/control.c b/src/feature/control/control.c
index b5d4c31525..ef707319a6 100644
--- a/src/feature/control/control.c
+++ b/src/feature/control/control.c
@@ -74,6 +74,18 @@ TO_CONTROL_CONN(connection_t *c)
   return DOWNCAST(control_connection_t, c);
 }
 
+/**
+ * Cast a `const connection_t *` to a `const control_connection_t *`.
+ *
+ * Exit with an assertion failure if the input is not a
+ * `control_connection_t`.
+ **/
+const control_connection_t *
+CONST_TO_CONTROL_CONN(const connection_t *c)
+{
+  return TO_CONTROL_CONN((connection_t*)c);
+}
+
 /** Create and add a new controller connection on <b>sock</b>.  If
  * <b>CC_LOCAL_FD_IS_OWNER</b> is set in <b>flags</b>, this Tor process should
  * exit when the connection closes.  If <b>CC_LOCAL_FD_IS_AUTHENTICATED</b>
diff --git a/src/feature/control/control.h b/src/feature/control/control.h
index 7e72b2736b..f884286ec7 100644
--- a/src/feature/control/control.h
+++ b/src/feature/control/control.h
@@ -13,6 +13,7 @@
 #define TOR_CONTROL_H
 
 control_connection_t *TO_CONTROL_CONN(connection_t *);
+const control_connection_t *CONST_TO_CONTROL_CONN(const connection_t *);
 
 #define CONTROL_CONN_STATE_MIN_ 1
 /** State for a control connection: Authenticated and accepting v1 commands. */
diff --git a/src/feature/dircommon/directory.c b/src/feature/dircommon/directory.c
index bb9264eaf9..e92e6480af 100644
--- a/src/feature/dircommon/directory.c
+++ b/src/feature/dircommon/directory.c
@@ -92,6 +92,18 @@ TO_DIR_CONN(connection_t *c)
   return DOWNCAST(dir_connection_t, c);
 }
 
+/**
+ * Cast a `const connection_t *` to a `const dir_connection_t *`.
+ *
+ * Exit with an assertion failure if the input is not a
+ * `dir_connection_t`.
+ **/
+const dir_connection_t *
+CONST_TO_DIR_CONN(const connection_t *c)
+{
+  return TO_DIR_CONN((connection_t *)c);
+}
+
 /** Return false if the directory purpose <b>dir_purpose</b>
  * does not require an anonymous (three-hop) connection.
  *
diff --git a/src/feature/dircommon/directory.h b/src/feature/dircommon/directory.h
index 0f26cdeff9..0aa2ff53ef 100644
--- a/src/feature/dircommon/directory.h
+++ b/src/feature/dircommon/directory.h
@@ -13,6 +13,7 @@
 #define TOR_DIRECTORY_H
 
 dir_connection_t *TO_DIR_CONN(connection_t *c);
+const dir_connection_t *CONST_TO_DIR_CONN(const connection_t *c);
 
 #define DIR_CONN_STATE_MIN_ 1
 /** State for connection to directory server: waiting for connect(). */