How to propagate data from mod-auth-external authenticator to served page - apache

Background
In our Apache configuration we use mod-auth-external (previously on Google Code) to invoke PAM authentication.
Now there is a request for proper handling of shadow-based password expiration:
If password is before warning period Apache should respond with HTTP status code 200. Nothing new here.
If password is in warning period (its validity end is near) Apache should respond with HTTP status code 200, but include somehow information about the warning period.
If password is in expiration period (it is no longer valid but user can still change it on his own) Apache should respond with HTTP status code 401 and include somehow information about expiration period.
If password is beyond expiration period (it is no longer valid and account was locked, administrator must unlock it) Apache should respond with HTTP status code 401 and include somehow information about the locked state.
(There are also corner cases of page missing or some other errors. It is not clear what to do then. But it seems that solving above points would allow to solve those corner cases as well.)
Our PAM authenticator (used through mod-auth-external) is able to differentiate those cases by adjusting return values. That we already have.
The problem is however how to get information from the authenticator to the associated action serving the page (either actual page with 200 status code or 401 error document).
Current investigations
It should be noted that there is significant difference between requirement 2 and requirements 3 and 4.
Requirements 3 and 4 alone are somewhat easier because they both involve our mod-auth-external authenticator returning error (access denied). So we only need to know how to get that error code in 401 error page. I even raised issue on that on mod-auth-external page.
Requirement 2 is much more difficult. In that case our authenticator must return 0 (access granted) and still somehow propagate information about the warning to whatever gets served in the end.
Logs parsing
Obvious (and ugly) idea is to parse logs. mod-auth-external description on Google Code Wiki mentions that authenticator return value gets written to Apache syslog. Also whatever authenticator prints to standard error stream gets logged as well.
This could be used to pass information from authenticator to some other entities.
The difficulty here is that it is not clear how to do it safely. What to print to be sure that "the other entity" will match properly current request with log entry. Mere URL doesn't seem to be enough since there can be multiple requests for the same URL at the same time. While I don't see anything more useful in what authenticator gets.
Another issue here is that it seems that to be able to parse the logs you have to have some non-trivial code running for "the other entity". And this complicates things further since how should we do it?
Another idea
If we could make the authenticator somehow modify "request session" (or whatever, maybe just environment? - I don't know, I'm new to Apache) to add arbitrary data to it we would be (almost) at home.
Our authenticator would somehow store "password status" and also possibly days remaining to the end of warning/expiration period (if applicable). Then upon serving 401 error page we would retrieve that back and use it to dynamically generate content of the page.
Or even better we would have it stored in session so that the other end could read that data directly. (For cases where it is not simply a browser showing page.)
But so far I fail to see how to do that.
Do you have any idea how to meet those requirements?

For over a month I got no answer here. Nor on GitHub issue that I opened for mod-auth-external.
So I ended doing a custom modification to our mod-auth-external. I don't like modifying third party software but this one seems dead anyway. And also it turned out we are using pretty old version (2.2.9 which I upgraded to 2.2.11, the last in 2.2.x line). Which already had some customizations anyway.
I explained details of the solution in a comment to my GitHub issue so I will not repeat them here.
I will however comment on shadow details as they were not mentioned there.
I had two choices: either use getspnam function to retrieve shadow data or to parse messages generated by PAM. First attempts based on getspnam function but in the end I used PAM messages. I didn't have strong reasons for any of those. However I decided to propagate in HTTP response not only shadow status but any PAM message that was generated and so it seemed easier to follow that way.

Related

Should an automatically performed once-a-day operation for users be responded with an error code from the server for further attempts?

I'm working on a project in which users automatically gain points if it's been more than 24h since their last login and a friendly message appears on the screen telling them that. If they log in again, nothing happens. But for me, as the dev of the project, I get a lot of scary red error messages in the browser logs showing me that a forbidden action has been tried, because when the backend detects that already made the transaction, it returns a 403, and this happens every time someone logs in or close and reopens the site.
I'm a bit confused whether this should really be the treatment for the case and wondering about how messed up error statistics of the site could get because of things like this, where nobody actually tried to perform a forbidden action, just the scheduled predictable behavior of the platform.
Should I change it to a 2xx status code?

Client does not want invalid logins to redirect

I would like to ask this question to developers who have a good sense of design. I see that whenever a website uses a popup box for their login page, they will always post and then redirect to the next page whether it be content or a dedicated login page for an invalid login error.
I have a client who has been asking to cut out as much page refreshing as possible, including the login function. They would like to see the login error appear on the login popup box without a page refresh.
I have not noticed a web based businesses do this, so I'm wondering if there's a valid reason to avoid this. I personally think that a page refreshing allows users to recognize their input has been registered and the next page appearing will be a solid response to their action either good or bad.
Having no refresh and expecting the user to notice that some error text has appeared seems like a bad idea?
Notes
The question is most likely more appropriate for https://ux.stackexchange.com .
You can find a lot of stuff by searching "ajax logins" in a search engine
There already is this question that might indeed be a duplicate of this one. Since I was not sure and I had already wrote most of this answer before finding that I post it nonetheless.
The title ought to be changed to a question (maybe something like "Is it a bad idea to use ajax to return login errors?").
Actual Answer
In my opinion ajax logins could indeed make less clear whether there really has been a successful interaction with the server or not.
Some ideas to improve it might be:
to include the time of the login request in the error message
to explicitly assure in the error message that the credentials have been received and checked
to be sure that this error does indeed only occur after the credentials have been determined to be not valid (and not because of problems with scripts or the network, for example).
A good way to ensure this might be to have the server always send the full text of the error, rather than a code that selects a message stored in the page source (and to be careful its caching).
This becomes relevant only after the user has been using the site for some time, of course (and has incurred in the error and verified that it was indeed due to a mistake on his part).
to use some animated feedback to highlight the dispatch and the reception of the reply to the user. As with the text you should ensure that the animations do not give (too) incorrect indications.
Basically these suggestions would be applicable to any ajax form entry, but they are more important for logins because:
in this context it's a lot easier to make typing mistakes (in the typing of the password)
and mistakes have a drastic, immediate annoying outcome: the inability to authenticate and the necessity to input again the entire password
And so uncertainties on whether the input has really been received and processed are a lot more bothering.
All in all anyhow it's pretty complex to do this well, with both an appealing appearance and a reassuring feedback.
The ones ajax logins that I've incurred into did not do a good job (I think I have indeed experienced false login errors with them).
You can find several ajax login frameworks/plugins by searching for "ajax logins". I have not looked into any of them.

"__RequestVerificationToken is not present" error when I can clearly see it in Developer tools

I'm trying to a CSRF protection to an existing MVC4 web application which uses DevExpress grids. I've added the Html.AntiForgeryToken() into the forms on the aspx pages (which contain ascx as partials containing the grids) and can see the __RequestVerificationToken and it's value clearly in developer tools when a save is called.
I've tried commenting out all my ValidateAntiForgeryToken attributes bar one - I went with the delete post method for simplicity (And also to eliminate the DevExpress grids messing with it) and I still keep coming up against this error:
There was a HttpAntiForgeryException
Url: http://localhost:54653/Users/Delete/f86ad393-0039-44e8-beed-a66dbab9266e?ReturnURL=http%3A%2F%2Flocalhost%3A54653%2FUsers
The exception message is
The required anti-forgery form field "__RequestVerificationToken" is not present.
Does anyone have any idea why this might be happening? Could it be that the error is non-descriptive and it's actually that the token doesn't match rather than that it doesn't exist? In previous answers to this question people just say "oh, you have to add the token," which is obviously not helpful here.
Are you submitting the form manually through Ajax? If that's the case, you need to pass the anti forgery token as another parameter with the name "__RequestVerificationToken".
Point 1 : Make sure if your application is has https secure protocol. Please load in https.
Point 2 : In case of DevExpress you have to call in the below pattern.
ViewContext.Writer.Write(Html.AntiForgeryToken().ToHtmlString());
After struggling with this for days I had a thought - maybe the browser is stopping the cookie being written. I did a search for dev servers and cookies not being written, and found that with Chrome and IE10 and up that there's problems writing the cookies.
I downloaded Firefox and tried it with that and it worked instantly. I then reapplied all the validate attributes to the all the controller methods and the all worked, every single one of them! Even the DexExpress postbacks seem to be working correctly.
I'll carry out more exhaustive testing, but for now, I think we're there.
Not exactly. If MVC AntiForgeryToken is already defined on page where you are using MvcxGridView and you want to protect grid actions you should send this token back to server during grid client side begin callback event.
settings.ClientSideEvents.BeginCallback = "function(s,e) { e.customArgs[\"__RequestVerificationToken\"] = $('input[name=\"__RequestVerificationToken\"]', $(s.GetMainElement())).val(); }";

Accessing Metacritic API and/or Scraping

Does anybody know where documentation for the Metacritic api is/if it still works. There used to be a Metacritic API at https://market.mashape.com/byroredux/metacritic-v2#get-user-details which disappeared today.
Otherwise I'm trying to scrape the site myself but keeping getting a blocked by a 429 Slow down. I got data like 3 times this hour and haven't been able to get anymore in the last 20 minutes which is making testing difficult and application possibly useless. Please let me know if there's anything else I can be doing to scape I don't know about.
I was using that API as well for an app I wrote a while ago. Looks like the creator removed it from Mashape. I just sent him an email to ask whether it'll be back up. I did find this scraper online. It only has a few endpoints but following the examples given you could easily add more. Let me know if you make any progress!
Edit: Looks like CBS requested it to be taken down. The ToS prohibits scraping:
[…] you agree not to do the following, or assist others to do the following:
Engage in unauthorized spidering, “scraping,” data mining or harvesting of Content, or use any other unauthorized automated means to gather data from or about the Services;
Though I was hoping for a Javascript way of doing this, the creator of the API also told me some info.
He says I was getting blocked for not having a User agent in the header and should use a 429 handling procedure i.e. re-request with longer pauses in between.
A PHP plugin available as well: http://datalinx.io/shop/metacritic-api/
I had to add a user agent like JCDJulian said and now it allows me to scrape. So for Ruby:
agent = Mechanize.new
agent.user_agent_alias = "Mac Firefox"
Then it stopped giving me the 403 Forbidden error.

How to do display security check authorization?

I am working around permission model in my project so when a particular user is not authorized then a screen is displayed depicting that the a user is not authorized to access the screen (which according to my best knowledge comes from a ArtifactExecutionFacadeImpl.groovy).
Is there any possible way to show that catch that exception and show it in a message.
So could you please suggest a way to do the same.
The current code returns a 401 (unauthorized) error when the authz fails (see MoquiServlet.groovy:68). You can display a custom screen with a code change instead of just returning the 401 error, or you can modify the web.xml file to specify a page to render for that particular response code (just like you can as part of the Servlet spec for any response code through the web.xml file).
Rendering a configured screen would be a useful enhancement to the framework (would be much cleaner and more flexible than either of the approaches mentioned above). I'll think on this and may work on it in the near future. If you or anyone end up building this, feel free to send over a pull request on GitHub and I'll take a look at it.