static int iscsi_target_handle_csg_zero()

in iscsi/iscsi_target_nego.c [818:907]

• 78 lines of code
• 18 McCabe index (conditional complexity)

static int iscsi_target_handle_csg_zero(
	struct iscsi_conn *conn,
	struct iscsi_login *login)
{
	int ret;
	u32 payload_length;
	struct iscsi_param *param;
	struct iscsi_login_req *login_req;
	struct iscsi_login_rsp *login_rsp;

	login_req = (struct iscsi_login_req *) login->req;
	login_rsp = (struct iscsi_login_rsp *) login->rsp;
	payload_length = ntoh24(login_req->dlength);

	param = iscsi_find_param_from_key(AUTHMETHOD, conn->param_list);
	if (!param)
		return -1;

	ret = iscsi_decode_text_input(
			PHASE_SECURITY|PHASE_DECLARATIVE,
			SENDER_INITIATOR|SENDER_RECEIVER,
			login->req_buf,
			payload_length,
			conn);
	if (ret < 0)
		return -1;

	if (ret > 0) {
		if (login->auth_complete) {
			pr_err("Initiator has already been"
				" successfully authenticated, but is still"
				" sending %s keys.\n", param->value);
			iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
					ISCSI_LOGIN_STATUS_INIT_ERR);
			return -1;
		}

		goto do_auth;
	} else if (!payload_length) {
		pr_err("Initiator sent zero length security payload,"
		       " login failed\n");
		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
				    ISCSI_LOGIN_STATUS_AUTH_FAILED);
		return -1;
	}

	if (login->first_request)
		if (iscsi_target_check_first_request(conn, login) < 0)
			return -1;

	ret = iscsi_encode_text_output(
			PHASE_SECURITY|PHASE_DECLARATIVE,
			SENDER_TARGET,
			login->rsp_buf,
			&login->rsp_length,
			conn->param_list,
			conn->tpg->tpg_attrib.login_keys_workaround);
	if (ret < 0)
		return -1;

	if (!iscsi_check_negotiated_keys(conn->param_list)) {
		if (conn->tpg->tpg_attrib.authentication &&
		    !strncmp(param->value, NONE, 4)) {
			pr_err("Initiator sent AuthMethod=None but"
				" Target is enforcing iSCSI Authentication,"
					" login failed.\n");
			iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
					ISCSI_LOGIN_STATUS_AUTH_FAILED);
			return -1;
		}

		if (conn->tpg->tpg_attrib.authentication &&
		    !login->auth_complete)
			return 0;

		if (strncmp(param->value, NONE, 4) && !login->auth_complete)
			return 0;

		if ((login_req->flags & ISCSI_FLAG_LOGIN_NEXT_STAGE1) &&
		    (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT)) {
			login_rsp->flags |= ISCSI_FLAG_LOGIN_NEXT_STAGE1 |
					    ISCSI_FLAG_LOGIN_TRANSIT;
			login->current_stage = 1;
		}
	}

	return 0;
do_auth:
	return iscsi_target_do_authentication(conn, login);
}