if(ctx->md_data) memset(ctx->md_data,0,ctx->digest->ctx_size);
int EVP_MD_CTX_cleanup(EVP_MD_CTX *ctx)	{	/* assume ctx->md_data was cleaned in EVP_Digest_Final */	OPENSSL_free(ctx->md_data);	memset(ctx,'\0',sizeof *ctx);	return 1;	}