Solution for Cross-domain Access in kkfileview File Stream Preview

# 1. Problem Background

1.1 Introduction to Cross-domain Access Issues

Cross-domain access is a common issue in internet application development. Cross-domain refers to accessing resources under a different domain name within the same browser, at which point the browser will block cross-domain requests to ensure security. The main reason for cross-domain access issues is the browser's same-origin policy, a set of rules established to protect user data security.

Security issues related to cross-domain access are a critical area of consideration for developers, with common threats including Cross-Site Scripting (XSS) attacks and Cross-Site Request Forgery (CSRF) attacks. Developers must take measures to prevent these security threats and ensure the security of their application systems.

In the following sections, we will delve into cross-domain access issues and their solutions to help developers better address the security concerns of cross-domain access.

# 2. Solution Exploration

2.1 Cross-domain Access Solutions Based on Proxy Services

Cross-domain access issues revolve around the browser's same-origin policy, which restricts how documents or scripts loaded from one source can interact with resources from another source. When dealing with cross-domain requests, proxy services can be utilized to help solve this problem.

#### 2.1.1 What are Proxy Services

A proxy service acts as an intermediary, where the client sends a request to the proxy, and the proxy then forwards the request to the target server and returns the server's response to the client. Proxy services are used in cross-domain requests to hide the client's real request address, thus bypassing the browser's same-origin policy restrictions.

##### *.*.*.* Analysis of Proxy Service Principles

The principle of proxy services is based on the "relay" action between the client and the target server, turning cross-domain requests into same-domain requests by forwarding them through the proxy server. This can be done without setting up CORS policies on the server side.

##### *.*.*.* Advantages and Limitations of Proxy Services

The advantage of proxy services lies in their simplicity and lack of requirements for the target server; however, they also come with increased latency and a need for higher network stability.

#### 2.1.2 Using Proxy Services to Solve Cross-domain Access Issues

In kkfileview, we can integrate proxy services to handle cross-domain requests, facilitating data exchange between the browser and the target server.

##### *.*.*.* Integrating Proxy Services in kkfileview

By integrating proxy services in kkfileview, requests can be intercepted and forwarded through the proxy server to the target server, with the response then returned to the client.

##### *.*.*.* Steps to Configure Proxy Services

1. Install proxy service software such as Nginx or Node.js;
2. Configure the forwarding rules of the proxy service, specifying the target server address;
3. Start the proxy service to listen on the specified port;
4. Modify the request address in the kkfileview front-end code to the proxy service address.

2.2 Security Considerations and Solutions

When using proxy services to solve cross-domain access issues, it is necessary to consider the security of data transmission to prevent the proxy service from being maliciously utilized or data from being leaked.

#### 2.2.1 Preventing Abuse of Proxy Services

To prevent proxy services from being abused, it is necessary to implement an authentication mechanism and access control permissions to ensure that only authorized users can use proxy services for cross-domain requests.

##### *.*.*.* Authentication Mechanism

Implement user authentication through methods such as username and password verification, Token verification, etc., so that only authenticated users can use proxy services.

##### *.*.*.* Access Control Permissions

Limit user access permissions to proxy services, perform access control based on user identity and permission levels, and prevent unauthorized users from making cross-domain requests.

#### 2.2.2 Encryption Processing of Data Transmission

To ensure the security of data transmission, the HTTPS protocol can be used to encrypt data transmission, using appropriate encryption algorithms during data transmission to ensure the confidentiality and integrity of the data.

##### *.*.*.* Application of HTTPS Protocol

Using the HTTPS protocol can encrypt data transmission, ensuring that data is not intercepted or tampered with during transmission, thereby improving the security of data