How to get/set the principal and session attributes from Spring 4 stomp websocket methods - spring

Question

I'm doing experiments with Spring 4 websockets and stomp, and I have a hard time figuring out how to get/set the current user and other session attributes in a message handling method annotated with #MessageMapping.
The documentation says that the message handling methods can take a Principal as argument, and I found that the principal is retrieved by Spring by calling getUserPrincipal() on the native socket session, and then associated with the socket session, but I haven't found any way to easily customize this behavior, other than writing a servlet filter and wrap the original request into a wrapper returning the principal found in my cookie.
So my questions are:
How to manually set the principal to the socket session, when the client connects (I have this information thanks to a custom cookie, and I don't use Spring security)?
If 1 is not possible, how to add additional attributes to the socket session when the client connects?
How to access the socket session and its attributes from a message handling method?
Is there a way to access the login and passcode sent by the browser at connection time. They seem to be completely ignore by Spring and not accessible.

Answer 1

UPDATE: With Spring 4.1 it is possible to set the user on the handshake for #1 from above. Per the Spring documentation you can create a new class which extends DefaultHandshakeHandler and override the determineUser method. Additionally you can also create a security filter which sets the principal as well if you have a token. I have implemented the second one myself and I include some sample code for both below.
For #2 and #3 I do not think that it is possible still. For #4 Spring intentionally ignores these per the documentation here.
SAMPLE CODE FOR DefaultHandshakeHandler SUBCLASS:
#Configuration
#EnableWebSocketMessageBroker
public class ApplicationWebSocketConfiguration extends AbstractWebSocketMessageBrokerConfigurer {
public class MyHandshakeHandler extends DefaultHandshakeHandler {
#Override
protected Principal determineUser(ServerHttpRequest request, WebSocketHandler wsHandler,
Map<String, Object> attributes) {
// add your own code to determine the user
return null;
}
}
#Override
public void registerStompEndpoints(StompEndpointRegistry registry) {
registry.addEndpoint("/myEndPoint").setHandshakeHandler(new MyHandshakeHandler());
}
}
SAMPLE CODE FOR SECURITY FILTER:
public class ApplicationSecurityTokenFilter extends GenericFilterBean {
private final static String AUTHENTICATION_PARAMETER = "authentication";
#Override
public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
if (servletRequest instanceof HttpServletRequest) {
// check to see if already authenticated before trying again
Authentication existingAuth = SecurityContextHolder.getContext().getAuthentication();
if ((existingAuth == null) || !existingAuth.isAuthenticated()) {
HttpServletRequest request = (HttpServletRequest)servletRequest;
UsernamePasswordAuthenticationToken token = extractToken(request);
// dump token into security context (for authentication-provider to pick up)
if (token != null) { // if it exists
SecurityContextHolder.getContext().setAuthentication(token);
}
}
}
filterChain.doFilter(servletRequest,servletResponse);
}
private UsernamePasswordAuthenticationToken extractToken( HttpServletRequest request ) {
UsernamePasswordAuthenticationToken authenticationToken = null;
// do what you need to extract the information for a token
// in this example we assume a query string that has an authenticate
// parameter with a "user:password" string. A new UsernamePasswordAuthenticationToken
// is created and then normal authentication happens using this info.
// This is just a sample and I am sure there are more secure ways to do this.
if (request.getQueryString() != null) {
String[] pairs = request.getQueryString().split("&");
for (String pair : pairs) {
String[] pairTokens = pair.split("=");
if (pairTokens.length == 2) {
if (AUTHENTICATION_PARAMETER.equals(pairTokens[0])) {
String[] tokens = pairTokens[1].split(":");
if (tokens.length == 2) {
log.debug("Using credentials: " + pairTokens[1]);
authenticationToken = new UsernamePasswordAuthenticationToken(tokens[0], tokens[1]);
}
}
}
}
}
return authenticationToken;
}
}
// set up your web security for the area in question
#Configuration
public class SubscriptionWebSecurityConfigurationAdapter extends WebSecurityConfigurerAdapter {
protected void configure(HttpSecurity http) throws Exception {
http
.requestMatchers().antMatchers("/myEndPoint**","/myEndPoint/**").and()
.addFilterBefore(new ApplicationSecurityTokenFilter(), UsernamePasswordAuthenticationFilter.class)
.authorizeRequests()
.anyRequest().authenticated()
.and()
.httpBasic() // leave this if you want non web browser clients to connect and add an auth header
.and()
.csrf().disable();
}
}
** NOTE: ** DO NOT declare your filter as a Bean. If you do then it will also be picked up (at least using Spring Boot) in the generic filters so it will fire on every request.

Answer 2

This is impossible for the time being (Spring 4.0). An issue has been opened (and considered) at Spring: https://jira.springsource.org/browse/SPR-11228