EVP_DecryptInit_ex (ctx, tr_encr->cipher, 0, 0, 0);
EVP_CIPHER_CTX_ctrl (ctx, EVP_CTRL_GCM_SET_IVLEN, 12, 0);
EVP_DecryptInit_ex (ctx, 0, 0, key, nonce);
EVP_DecryptUpdate (ctx, 0, &len, aad, aad_len);
EVP_DecryptInit_ex (ctx, tr_encr->cipher, 0, 0, 0);
EVP_CIPHER_CTX_ctrl (ctx, EVP_CTRL_GCM_SET_IVLEN, 12, 0);
EVP_DecryptInit_ex (ctx, 0, 0, key, nonce);
EVP_DecryptUpdate (ctx, 0, &len, aad, aad_len);