How to Integrate JCaptcha in Spring Security

The repository for JCaptcha is this one:

<repository>
<id>sourceforge-releases</id>
<name>Sourceforge Releases</name>
<url>https://oss.sonatype.org/content/repositories/sourceforge-releases</url>
</repository>

<dependency>
<groupId>com.octo.captcha</groupId>
<artifactId>jcaptcha-integration-simple-servlet</artifactId>
<version>2.0-alpha-1</version>
</dependency>

Here are some configuration I made in .xml files:

web.xml

<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>
/WEB-INF/applicationContext.xml
/WEB-INF/spring/spring-security.xml
</param-value>
</context-param>
<listener>
<listener-class>org.springframework.security.web.session.HttpSessionEventPublisher</listener-class>
</listener>

<filter>
<filter-name>springSecurityFilterChain</filter-name>
<filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
</filter>

<filter-mapping>
<filter-name>springSecurityFilterChain</filter-name>
<url-pattern>/*</url-pattern>
<dispatcher>FORWARD</dispatcher>
<dispatcher>REQUEST</dispatcher>
</filter-mapping>

<servlet>
<servlet-name>jcaptcha</servlet-name>
<servlet-class>com.octo.captcha.module.servlet.image.SimpleImageCaptchaServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>jcaptcha</servlet-name>
<url-pattern>/jcaptcha.jpg</url-pattern>
</servlet-mapping>

spring-security.xml

<http auto-config="true" use-expressions="true">
<intercept-url pattern="/resources/**" access="permitAll()" />
<intercept-url pattern="/jcaptcha.jpg" access="permitAll()" />
<intercept-url pattern="/**" access="isAuthenticated()" />

<form-login login-page="/session/login/" default-target-url="/"
authentication-failure-url="/session/loginfailed/" />
<logout logout-success-url="/session/logout/" />
<access-denied-handler error-page="/session/403/" />

<!--JCaptcha Filtering-->
<custom-filter ref="captchaCaptureFilter" before="FORM_LOGIN_FILTER"/>
<!-- REMOVED custom-filter ref="captchaVerifierFilter" after="FORM_LOGIN_FILTER"/-->
<anonymous />
</http>

<!-- For capturing CAPTCHA fields -->
<beans:bean id="captchaCaptureFilter" class="com.util.CaptchaCaptureFilter" />

<!-- For verifying CAPTCHA fields -->
<!-- Private key is assigned by the JCaptcha service -->
<!-- REMOVED beans:bean id="captchaVerifierFilter" class="com.util.CaptchaVerifierFilter"
p:failureUrl="/session/loginfailed/"
p:captchaCaptureFilter-ref="captchaCaptureFilter"/-->

<beans:property name="sessionAuthenticationStrategy" ref="sas"/>
<beans:property name="authenticationManager" ref="authenticationManager" />
<beans:property name="allowSessionCreation" value="true" />
</beans:bean>

<beans:bean id="sas" class="org.springframework.security.web.authentication.session.ConcurrentSessionControlStrategy">
<beans:constructor-arg name="sessionRegistry" ref="sessionRegistry"/>
<beans:property name="maximumSessions" value="1" />
</beans:bean>

<beans:bean id="sessionRegistry" class="org.springframework.security.core.session.SessionRegistryImpl" />

<beans:bean id="userService" class="com.service.mybatis.UserManager" />

<beans:bean id="customAuthenticationProvider" class="com.util.MyAuthenticationProvider" p:captchaCaptureFilter-ref="captchaCaptureFilter" />
<authentication-manager alias="authenticationManager">
<authentication-provider ref="customAuthenticationProvider" />
</authentication-manager>

<beans:bean id="accessDeniedHandler" class="com.util.ThouShaltNoPass">
<beans:property name="accessDeniedURL" value="/session/403/" />
</beans:bean>

And these are the java classes:

MyAuthenticationProvider.java

public class MyAuthenticationProvider implements AuthenticationProvider {

@Autowired
private UserService userService;
private Logger logger = LoggerFactory.getLogger(ArtajasaAuthenticationProvider.class);
private CaptchaCaptureFilter captchaCaptureFilter;

@Override
public Authentication authenticate(Authentication authentication) throws AuthenticationException {
String username = String.valueOf(authentication.getPrincipal());
String password = String.valueOf(authentication.getCredentials());
logger.debug("Checking authentication for user {}", username);
logger.debug("userResponse: {}", captchaCaptureFilter.getUserCaptchaResponse());
if (StringUtils.isBlank(username)
|| StringUtils.isBlank(password)) {
throw new BadCredentialsException("No Username and/or Password Provided.");
}
else if(StringUtils.isBlank(captchaCaptureFilter.getUserCaptchaResponse())) {
throw new BadCredentialsException("Captcha Response is Empty");
}
else {
// Send HTTP request to validate user's Captcha
boolean captchaPassed = SimpleImageCaptchaServlet.validateResponse(captchaCaptureFilter.getRequest(), captchaCaptureFilter.getUserCaptchaResponse());

// Check if valid
if (captchaPassed) {
logger.debug("Captcha is valid!");
resetCaptchaFields();

Pengguna user = userService.select(username);
if (user == null) {
throw new BadCredentialsException("Invalid Username and/or Password.");
}
if (user.getPassword().equals(new PasswordUtil().generateHash(password, user.getSalt()))) {
List<GrantedAuthority> authorityList = (List<GrantedAuthority>) userService.getAuthorities(user);
return new UsernamePasswordAuthenticationToken(username, password, authorityList);
}
else {
throw new BadCredentialsException("Invalid Username and/or Password.");
}
}
else {
logger.debug("Captcha is invalid!");
resetCaptchaFields();

throw new BadCredentialsException("Invalid Captcha.");
}
}
}

@Override
public boolean supports(Class<?> authentication) {
return (UsernamePasswordAuthenticationToken.class.isAssignableFrom(authentication));
}

/**
* Reset Captcha fields
*/
public void resetCaptchaFields() {
captchaCaptureFilter.setUserCaptchaResponse(null);
}

public CaptchaCaptureFilter getCaptchaCaptureFilter() {
return captchaCaptureFilter;
}

public void setCaptchaCaptureFilter(CaptchaCaptureFilter captchaCaptureFilter) {
this.captchaCaptureFilter = captchaCaptureFilter;
}
}

CaptchaCaptureFilter.java

public class CaptchaCaptureFilter extends OncePerRequestFilter {

private Logger logger = Logger.getLogger(CaptchaCaptureFilter.class);
private String userCaptchaResponse;
private HttpServletRequest request;

@Override
public void doFilterInternal(HttpServletRequest req, HttpServletResponse res,
FilterChain chain) throws IOException, ServletException {

logger.debug("Captcha capture filter");

// Assign values only when user has submitted a Captcha value.
// Without this condition the values will be reset due to redirection
// and CaptchaVerifierFilter will enter an infinite loop
if (req.getParameter("jcaptcha") != null) {
request = req;
userCaptchaResponse = req.getParameter("jcaptcha");
}

logger.debug("userResponse: " + userCaptchaResponse);

// Proceed with the remaining filters
chain.doFilter(req, res);
}

public String getUserCaptchaResponse() {
return userCaptchaResponse;
}

public void setUserCaptchaResponse(String userCaptchaResponse) {
this.userCaptchaResponse = userCaptchaResponse;
}

public HttpServletRequest getRequest() {
return request;
}

public void setRequest(HttpServletRequest request) {
this.request = request;
}
}

Last but not least, login.jsp

<%@ taglib prefix='c' uri='http://java.sun.com/jstl/core_rt' %>

<form id="login" name="f" action="<c:url value='/j_spring_security_check'/>" method="POST">
<div class="container">

<div class="content">
<div class="row">
<div class="login-form">
<h3>Login</h3>
<br />
<fieldset>
<div class="clearfix">
username: ecr
<input type="text" name='j_username' value='<c:if test="${not empty param.login_error}"><c:out value="${SPRING_SECURITY_LAST_USERNAME}"/></c:if>' placeholder="username@artajasa.co.id">
</div>
<div class="clearfix">
password: ecr123
<input type="password" name='j_password' placeholder="password">
</div>
<div class="clearfix">
<img src="../../jcaptcha.jpg" />
<br />
<input type="text" name="jcaptcha" placeholder="masukkan captcha" />
</div>
<br />
<button class="btn btn-primary" type="submit"><i class="icon-lock"></i> Sign in</button>
</fieldset>
</div>
</div>
</div>
<br />
<c:if test="${not empty error}">
<div class="alert alert-error">
<button type="button" class="close" data-dismiss="alert"><i class="icon-remove"></i></button>
Login Failed, try again.<br />
<c:out value="${sessionScope['SPRING_SECURITY_LAST_EXCEPTION'].message}"/>
</div>
</c:if>
</div>

done!