diff --git a/wolfssl/wolfcrypt/asn_public.h b/wolfssl/wolfcrypt/asn_public.h
index f55312c12..58350be2a 100644
--- a/wolfssl/wolfcrypt/asn_public.h
+++ b/wolfssl/wolfcrypt/asn_public.h
@@ -56,6 +56,10 @@ This library defines the interface APIs for X509 certificates.
 #endif
 #ifndef WC_RNG_TYPE_DEFINED
     typedef struct WC_RNG WC_RNG;
+    #ifdef WC_RNG_SEED_CB
+    typedef struct OS_Seed OS_Seed;
+    typedef int (*wc_RngSeed_Cb)(OS_Seed* os, byte* seed, word32 sz);
+    #endif
     #define WC_RNG_TYPE_DEFINED
 #endif