Filter Chain in SpringSecurity

In Spring Security, Filter Chain is the core of implementing request security control. Spring Security's security framework is based on Servlet filters, and different security features are achieved through a series of filters, such as authentication, authorization, etc.

What is Filter Chain

Filter Chain is a filter chain, which is a collection of a series of filters, each of which is responsible for handling different security logic. When a request arrives in the Spring application, it is processed in sequence by a series of filters configured in the Filter Chain, each filter performing its specific task.

Workflow

• Request to intercept: When a request arrives, it is first intercepted by Spring Security's Filter Chain.
• Filter processing: Requests pass through each filter in the Filter Chain in sequence. Each filter processes the request according to its responsibilities, such as verifying authentication information, checking user permissions, etc.
• Continue processing or terminate: If a request is considered legal and compliant with security requirements in a certain filter, it will continue to be passed to the next filter or reach its final destination (i.e., the controller). If intercepted by a filter (for example, authentication failure), the pass will no longer continue, but will return the response directly.

Common filters

Spring Security provides many built-in filters, and here are some common examples:

• SecurityContextPersistenceFilter: Keep in one requestSecurityContext(Security context) so that it is always available throughout the request processing process.
• UsernamePasswordAuthenticationFilter: Process form-based login requests.
• BasicAuthenticationFilter: Used to handle HTTP basic authentication.
• ExceptionTranslationFilter: Catch security-related exceptions, and then hand over these exceptions to the configured exception handling mechanism for processing.
• FilterSecurityInterceptor: This is the last filter in the filter chain, which is responsible for access control checking the request before calling the target resource.

Custom filters

You can also create custom filters to extend Spring Security to meet specific security needs. Custom filters can be implementedThe interface is created, and then you need to register this custom filter into Spring Security's Filter Chain.

public class CustomFilter extends GenericFilterBean {
    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        // Custom logic        (request, response);
    }
}

Integrate into Spring Security

To integrate custom filters into Spring Security, you can configure itHttpSecurityObject to implement:

@Override
protected void configure(HttpSecurity http) throws Exception {
    http
        // Configure other security details        .addFilterBefore(new CustomFilter(), ); // Example: Add a custom filter before UsernamePasswordAuthenticationFilter}

Summarize

Spring Security's Filter Chain is a pipeline consisting of a series of filters, each performing specific security functions. In this way, Spring Security can provide powerful and flexible security controls to protect your applications from various cybersecurity threats. By customizing filters and properly configuring Filter Chain, the security policies of applications can be highly customized.

This is all about this article about Filter Chain in SpringSecurity. For more related SpringSecurity Filter Chain content, please search for my previous articles or continue browsing the related articles below. I hope everyone will support me in the future!