diff --git a/include/mbedtls/ssl_internal.h b/include/mbedtls/ssl_internal.h
index 2b5a616..168d4a2 100644
--- a/include/mbedtls/ssl_internal.h
+++ b/include/mbedtls/ssl_internal.h
@@ -24,6 +24,12 @@
 #ifndef MBEDTLS_SSL_INTERNAL_H
 #define MBEDTLS_SSL_INTERNAL_H
 
+#if !defined(MBEDTLS_CONFIG_FILE)
+#include "config.h"
+#else
+#include MBEDTLS_CONFIG_FILE
+#endif
+
 #include "ssl.h"
 #include "cipher.h"