I found this guide for developing your own Server Authentication Module (SAM) for Glassfish: http://docs.oracle.com/cd/E18930_01/html/821-2418/gizel.html
It seems pretty straightforward to verify some credentials (in HTTP Auth headers for instance), but my question is this:
Can I develop my SAM in such a way that I can forward the user to a specific page if he's not logged in?
Here's the example from the guide:
package tip.sam;
import java.io.IOException;
import java.util.Map;
import javax.security.auth.Subject;
import javax.security.auth.callback.Callback;
import javax.security.auth.callback.CallbackHandler;
import javax.security.auth.callback.UnsupportedCallbackException;
import javax.security.auth.message.AuthException;
import javax.security.auth.message.AuthStatus;
import javax.security.auth.message.MessageInfo;
import javax.security.auth.message.MessagePolicy;
import javax.security.auth.message.callback.CallerPrincipalCallback;
import javax.security.auth.message.callback.GroupPrincipalCallback;
import javax.security.auth.message.callback.PasswordValidationCallback;
import javax.security.auth.message.module.ServerAuthModule;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.catalina.util.Base64;
public class MySam implements ServerAuthModule {
protected static final Class[]
supportedMessageTypes = new Class[]{
HttpServletRequest.class,
HttpServletResponse.class
};
private MessagePolicy requestPolicy;
private MessagePolicy responsePolicy;
private CallbackHandler handler;
private Map options;
private String realmName = null;
private String defaultGroup[] = null;
private static final String REALM_PROPERTY_NAME =
"realm.name";
private static final String GROUP_PROPERTY_NAME =
"group.name";
private static final String BASIC = "Basic";
static final String AUTHORIZATION_HEADER =
"authorization";
static final String AUTHENTICATION_HEADER =
"WWW-Authenticate";
public void initialize(MessagePolicy reqPolicy,
MessagePolicy resPolicy,
CallbackHandler cBH, Map opts)
throws AuthException {
requestPolicy = reqPolicy;
responsePolicy = resPolicy;
handler = cBH;
options = opts;
if (options != null) {
realmName = (String)
options.get(REALM_PROPERTY_NAME);
if (options.containsKey(GROUP_PROPERTY_NAME)) {
defaultGroup = new String[]{(String)
options.get(GROUP_PROPERTY_NAME)};
}
}
}
public Class[] getSupportedMessageTypes() {
return supportedMessageTypes;
}
public AuthStatus validateRequest(
MessageInfo msgInfo, Subject client,
Subject server) throws AuthException {
try {
String username =
processAuthorizationToken(msgInfo, client);
if (username ==
null && requestPolicy.isMandatory()) {
return sendAuthenticateChallenge(msgInfo);
}
setAuthenticationResult(
username, client, msgInfo);
return AuthStatus.SUCCESS;
} catch (Exception e) {
AuthException ae = new AuthException();
ae.initCause(e);
throw ae;
}
}
private String processAuthorizationToken(
MessageInfo msgInfo, Subject s)
throws AuthException {
HttpServletRequest request =
(HttpServletRequest)
msgInfo.getRequestMessage();
String token =
request.getHeader(AUTHORIZATION_HEADER);
if (token != null && token.startsWith(BASIC + " ")) {
token = token.substring(6).trim();
// Decode and parse the authorization token
String decoded =
new String(Base64.decode(token.getBytes()));
int colon = decoded.indexOf(':');
if (colon <= 0 || colon == decoded.length() - 1) {
return (null);
}
String username = decoded.substring(0, colon);
// use the callback to ask the container to
// validate the password
PasswordValidationCallback pVC =
new PasswordValidationCallback(s, username,
decoded.substring(colon + 1).toCharArray());
try {
handler.handle(new Callback[]{pVC});
pVC.clearPassword();
} catch (Exception e) {
AuthException ae = new AuthException();
ae.initCause(e);
throw ae;
}
if (pVC.getResult()) {
return username;
}
}
return null;
}
private AuthStatus sendAuthenticateChallenge(
MessageInfo msgInfo) {
String realm = realmName;
// if the realm property is set use it,
// otherwise use the name of the server
// as the realm name.
if (realm == null) {
HttpServletRequest request =
(HttpServletRequest)
msgInfo.getRequestMessage();
realm = request.getServerName();
}
HttpServletResponse response =
(HttpServletResponse)
msgInfo.getResponseMessage();
String header = BASIC + " realm=\"" + realm + "\"";
response.setHeader(AUTHENTICATION_HEADER, header);
response.setStatus(
HttpServletResponse.SC_UNAUTHORIZED);
return AuthStatus.SEND_CONTINUE;
// MAYBE SOMETHING HERE?
}
public AuthStatus secureResponse(
MessageInfo msgInfo, Subject service)
throws AuthException {
return AuthStatus.SEND_SUCCESS;
}
public void cleanSubject(MessageInfo msgInfo,
Subject subject)
throws AuthException {
if (subject != null) {
subject.getPrincipals().clear();
}
}
private static final String AUTH_TYPE_INFO_KEY =
"javax.servlet.http.authType";
// distinguish the caller principal
// and assign default groups
private void setAuthenticationResult(String name,
Subject s, MessageInfo m)
throws IOException,
UnsupportedCallbackException {
handler.handle(new Callback[]{
new CallerPrincipalCallback(s, name)
});
if (name != null) {
// add the default group if the property is set
if (defaultGroup != null) {
handler.handle(new Callback[]{
new GroupPrincipalCallback(s, defaultGroup)
});
}
m.getMap().put(AUTH_TYPE_INFO_KEY, ""MySAM");
}
}
}
Yes, you can do that in the validateRequest method.
Here is a simple example:
public AuthStatus validateRequest(MessageInfo messageInfo,
Subject clientSubject,
Subject serviceSubject) throws AuthException {
// clientSubject.getPrincipals() returns the principals
// check this set to know if the user is not logged in
// if the user is not logged in do the following
HttpServletResponse response = (HttpServletResponse) messageInfo.getResponseMessage();
response.sendRedirect("login.html");
}
It might be better to do it inside of a custom LoginModule (if you already know what that is), but I guess this depends on your requirements.
See also: