身份验证用户名和密码已加密，并从前端传输到后端

Question

预期行为

如何替换默认的UsernamePasswordAuthenticationFilter。

上下文

spring安全版本：5.1.4

问题：

1。用户名和密码被加密并从前端传输到后端。前端RSA加密。后端身份验证首先需要解密。

2.UsernamePasswordAuthenticationFilter

// Can't find how to inject into security
UsernamePasswordAuthenticationFilter

protected String obtainPassword(HttpServletRequest request) {
        return request.getParameter(passwordParameter);
    }

protected String obtainUsername(HttpServletRequest request) {
        return request.getParameter(usernameParameter);
    }

3.FormLoginConfigurer FormLoginConfigurer是最终类，无法继承。

构造函数初始化UsernamePasswordAuthenticationFilter，无法更改代码

public FormLoginConfigurer() {
        super(new UsernamePasswordAuthenticationFilter(), null);
        usernameParameter("username");
        passwordParameter("password");
    }

4.HttpSecurity

public final class HttpSecurity {
      public FormLoginConfigurer<HttpSecurity> formLogin() throws Exception {
        return getOrApply(new FormLoginConfigurer<>());
    }
}