int iscsi_target_check_login_request()

in iscsi/iscsi_target_nego.c [159:247]

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

int iscsi_target_check_login_request(
	struct iscsi_conn *conn,
	struct iscsi_login *login)
{
	int req_csg, req_nsg;
	u32 payload_length;
	struct iscsi_login_req *login_req;

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

	switch (login_req->opcode & ISCSI_OPCODE_MASK) {
	case ISCSI_OP_LOGIN:
		break;
	default:
		pr_err("Received unknown opcode 0x%02x.\n",
				login_req->opcode & ISCSI_OPCODE_MASK);
		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
				ISCSI_LOGIN_STATUS_INIT_ERR);
		return -1;
	}

	if ((login_req->flags & ISCSI_FLAG_LOGIN_CONTINUE) &&
	    (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT)) {
		pr_err("Login request has both ISCSI_FLAG_LOGIN_CONTINUE"
			" and ISCSI_FLAG_LOGIN_TRANSIT set, protocol error.\n");
		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
				ISCSI_LOGIN_STATUS_INIT_ERR);
		return -1;
	}

	req_csg = ISCSI_LOGIN_CURRENT_STAGE(login_req->flags);
	req_nsg = ISCSI_LOGIN_NEXT_STAGE(login_req->flags);

	if (req_csg != login->current_stage) {
		pr_err("Initiator unexpectedly changed login stage"
			" from %d to %d, login failed.\n", login->current_stage,
			req_csg);
		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
				ISCSI_LOGIN_STATUS_INIT_ERR);
		return -1;
	}

	if ((req_nsg == 2) || (req_csg >= 2) ||
	   ((login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT) &&
	    (req_nsg <= req_csg))) {
		pr_err("Illegal login_req->flags Combination, CSG: %d,"
			" NSG: %d, ISCSI_FLAG_LOGIN_TRANSIT: %d.\n", req_csg,
			req_nsg, (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT));
		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
				ISCSI_LOGIN_STATUS_INIT_ERR);
		return -1;
	}

	if ((login_req->max_version != login->version_max) ||
	    (login_req->min_version != login->version_min)) {
		pr_err("Login request changed Version Max/Nin"
			" unexpectedly to 0x%02x/0x%02x, protocol error\n",
			login_req->max_version, login_req->min_version);
		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
				ISCSI_LOGIN_STATUS_INIT_ERR);
		return -1;
	}

	if (memcmp(login_req->isid, login->isid, 6) != 0) {
		pr_err("Login request changed ISID unexpectedly,"
				" protocol error.\n");
		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
				ISCSI_LOGIN_STATUS_INIT_ERR);
		return -1;
	}

	if (login_req->itt != login->init_task_tag) {
		pr_err("Login request changed ITT unexpectedly to"
			" 0x%08x, protocol error.\n", login_req->itt);
		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
				ISCSI_LOGIN_STATUS_INIT_ERR);
		return -1;
	}

	if (payload_length > MAX_KEY_VALUE_PAIRS) {
		pr_err("Login request payload exceeds default"
			" MaxRecvDataSegmentLength: %u, protocol error.\n",
				MAX_KEY_VALUE_PAIRS);
		return -1;
	}

	return 0;
}