-void HMAC_Init(HMAC_CTX *ctx, const void *key, int len,
- const EVP_MD *md);
-void HMAC_Update(HMAC_CTX *ctx,unsigned char *key, int len);
-void HMAC_Final(HMAC_CTX *ctx, unsigned char *md, unsigned int *len);
-void HMAC_cleanup(HMAC_CTX *ctx);
+/* deprecated */
+int HMAC_Init(HMAC_CTX *ctx, const void *key, int len, const EVP_MD *md);
+int HMAC_Init_ex(HMAC_CTX *ctx, const void *key, int len,
+ const EVP_MD *md, ENGINE *impl);
+int HMAC_Update(HMAC_CTX *ctx, const unsigned char *data, size_t len);
+int HMAC_Final(HMAC_CTX *ctx, unsigned char *md, unsigned int *len);