+int EVP_DigestSignInit(EVP_MD_CTX *ctx, EVP_PKEY_CTX **pctx,
+ const EVP_MD *type, ENGINE *e, EVP_PKEY *pkey);
+int EVP_DigestSignFinal(EVP_MD_CTX *ctx,
+ unsigned char *sigret, size_t *siglen);
+
+int EVP_DigestVerifyInit(EVP_MD_CTX *ctx, EVP_PKEY_CTX **pctx,
+ const EVP_MD *type, ENGINE *e, EVP_PKEY *pkey);
+int EVP_DigestVerifyFinal(EVP_MD_CTX *ctx,
+ unsigned char *sig, size_t siglen);
+