typedef struct evp_kdf_st EVP_KDF;
typedef struct evp_kdf_ctx_st EVP_KDF_CTX;
+typedef struct evp_rand_st EVP_RAND;
+typedef struct evp_rand_ctx_st EVP_RAND_CTX;
+
typedef struct evp_keyexch_st EVP_KEYEXCH;
typedef struct evp_signature_st EVP_SIGNATURE;