diff --git a/configs/config-symmetric-only.h b/configs/config-symmetric-only.h
index 28150d6..c883596 100644
--- a/configs/config-symmetric-only.h
+++ b/configs/config-symmetric-only.h
@@ -85,6 +85,7 @@
 #define MBEDTLS_RIPEMD160_C
 #define MBEDTLS_SHA1_C
 #define MBEDTLS_SHA256_C
+#define MBEDTLS_SHA224_C
 #define MBEDTLS_SHA512_C
 #define MBEDTLS_SHA384_C
 //#define MBEDTLS_THREADING_C