The general answer you can find everywhere is to use the Signal authenticationRequired(QNetworkReply*, QAuthenticator*), then fill the login credentials into the given QAuthenticator object.
However, this does not work in my case as that signal is never emitted. Reason: The server does not return an authorization failure but redirects me to a login page instead. So my program will just download that page.
I have found out how to catch this by checking the attribute QNetworkRequest::RedirectionTargetAttribute of the QNetworkReply.
So I can detect the redirection and ask the user for auth info.
But... where do I go from there? How do I set the authentication data? Can I manually set a QAuthenticator to my QNetworkRequest or my QNetworkAccessManager? I didn't find a way to do that anywhere, just via the above-mentioned signal/slot mechanism which does not work because it does not trigger.
Any help would be greatly appreciated!
From documentation,
http://qt-project.org/doc/qt-5/qauthenticator.html
QAuthenticator supports the following authentication methods:
Basic
NTLM version 2
Digest-MD5
Since you are getting redirected to a login page, and you haven't indicated if any of the above authentication methods even works, I will assume that it does not because things like Basic authentication is sent on every request to the server. Login pages generally authenticate the client and use some sort of a cookie for future authentication. To do this,
Detect login page
Pass proper credentials to the server (based on what the form wants)
In the QNetworkReply to the login page, look for cookies (Set-Cookie headers).
Pass the relevant cookies back with your requests.
If it works, you are no longer redirected to login page.
For information on cookies, you can get overview via Wikipedia, but for implementation, you need to look at the RFC 6265,
If this is incorrect, and you can use basic authentication, then that information is passed in the URL itself. Set username and password in your QUrl and if it works, you will not be redirected. http://qt-project.org/doc/qt-5/qurl.html#setPassword
Related
I'm new to web development and trying to get my feet wet by building a web app that uses Google APIs. I was reading Google's documentation on using OAuth 2.0, but the redirect URL bit has me a bit confused. According to the example here a successful authentication will send a response to
{redirect_url}?state=/profile&code={auth_code}
The response URL doesn't specify a user and neither does the response load as far as I know. How does the redirect URL endpoint know which user is tied to the authorization code it just received?
There was a very similar question here, but the answers focus on passing query parameters to the redirect URL. I'm not trying to do that. I want to understand how the redirect endpoint associates an OAuth response to a particular user. Note that I'm pretty new to all of this, so my confusion might stem from not understanding how HTTPS calls work or something similar.
A notable detail is when your redirect URL receives a response with code, it is the Google authorization server that redirect user's browser to your server. So it's user's browser that send a request to your server with code.
In other word, actually, you question is: "When your server receives many requests from many users, how do you know which user a request comes from"
I think you need to learn something about session or cookie which allows
HTTP to become stateful.
I have implemented an OAuth2 authentication mechanism in my GWT app. The OAuth2 server is based on Spring framework 3.x (using its Spring security OAuth2 implementation).
I am using the OAuth2 "Authorization code flow" to get the user authenticated (though implicit flow may have been a better choice in our case). So at first, the user is redirected to the OAuth2 server authentication page, he enters his credentials and if he is successfully authenticated, he is redirected back to a url with an oauth code. He will then make a second call to get an access token from the OAuth2 server.
Now, the issue is, we would like the user to be able to bookmark a page in the application and directly access it. If he has already authenticated then he would have direct access to it (no more auth involved). Otherwise, he would have to go into the OAuth2 authentication flow but in the end, should be redirected back to the bookmarked page he intended to access at the beginning.
How can I store this page url and get redirected to it after the user successfully authenticates ?
any help would be appreciated. Thanks!
EDITED
The initial url redirection is done via javascript's document.location.href
The way to maintain the original URI in an OAuth 2.0 Authorization Grant flow is to pass it in the state parameter so that the redirection endpoint can use it, after it exchange the authorization code for an access token, to redirect the user back to that URI.
FYI, this is exactly what Google suggests in the examples in their OAuth 2.0 documentation, e.g. https://developers.google.com/accounts/docs/OAuth2Login
Original answer:
The problem is using the hash part of the URL for the place, which is not sent to the server and thus cannot be used in the redirection to the OAuth2 server authentication page.
You have 2 (maybe 3) solutions:
stop using the hash for the place and switch to HTML5 History; either through gwt-pushstate at the History level, or a custom PlaceHistoryHandler.Historian if you use the Places API. That limits your audience though: http://caniuse.com/history
stop using an HTTP redirect, and instead use JavaScript so you can put the hash in the OAuth2 redirect_uri. So instead of redirecting, send an error page with the appropriate scripts bits.
some browsers append the hash to the URL after a redirection, so your OAuth2 server might be able to pick it (in JavaScript) and append it to the redirect_uri. That might depend on the HTTP status code used for redirecting (from experience, it works with a 301, but you don't want a 301 here). Needs testing.
You can do this using GWT activities and places.
I have a standard HTML login page, which I would much rather use than the standard HTTP authentication pop-up provided by browsers. Today, I am using session cookies to keep track of the session after logging in, but I'd like to be stateless and pass the HTTP authentication every time. The web services I am hitting already support this, so this is a browser-only issue.
Adding authentication credentials is trivial in jQuery, but I don't know how to keep them around. If you go from the login page (a jsp) to the Home page (another jsp) you clearly don't keep the username and password fields from the login page. I know some browsers will store your HTTP authentication credentials if you enter them from the pop-up, but I don't know if they get stored when using an XHRRequest. If they do, is there much consistency among browsers?
Also, the user needs to be able to "sign out" of the application, too. If the browser stores the authentication credentials, is there a way to clear them using JavaScript.
I feel like I can't be the first person to try to solve this. Is there some jQuery plugin or something that already handles this? Or is it simply not possible to do what I'm trying to do?
You have 2 options:
1) Client-side storage of credentials -- not a good idea. For obvious reasons you don't want to store the username/password on the client. If you had a hashed version of the password, it might not be so bad, but still not recommended. In any case, if you're going to store on the client side, you either have to use a cookie, or HTML5 local storage (which is not widely supported, yet)
2) Server-side storage of credentials -- typically done with sessions. Then the resultant Session ID can be passed back to the client and persisted in either a cookie or in the URL of each subsequent AJAX call (?SESSID=xyz for example)
The server-side approach would be the most secure, reliable, and easiest to implement
Okay, I'll take a stab at helping ...
Firstly, understand how HTTP authentication works. There are two versions - Basic and Digest. Basic transmits in plaintext, digest is encrypted. With these types of authentication, the username/password are passed in the HTTP header with every single request. The browser captures these at login and they are stored in an inaccessible browser session cookie which is deleted when the browser session is closed. So, in answer to one of your questions, you can't access these from javascript.
You could create your own session cookie variables for username and password. The jQuery functions for this are really simple. See jquery-cookie module as one example of how to set session cookies. These could be retrieved from the session cookie and sent with each ajax request and validated in the server. However, this is not a particulary good way to do authentication since sniffing the network will allow anybody to easily grab your auth details. But, it would work.
Using session cookie based authentication where the session ID is sent sent with each request is the best way to do this. At the server side, you need to have a function called for every HTTP request. This function should do the following:
check to see if the session has been authenticated
if no:
redirect to login screen
if yes:
do authorization and allow the user access to the page
Most web frameworks support session cookie authentication and the management of session ids at the server. This is definately the way to go.
This is interesting one.
Manage user sessions on server by use of cookies. Create a session when user first accesses the login page and pass the session id/key as value to one of the cookie via response. When the user is authenticated put user "key" info in cookie and "values" in application context at server. Once user is logged, any subsequent request will be authenticated based on session cookie value at server. Authorization will be done based on user "key" passed as cookie value.
On logout clear the session based cookies from server and refresh the site to default page.
Cookies are bizarre with different browsers - just a note ;)
Hope this helps.
Update
The answer below was posted in 2012 and the links are mostly dead. However, since then, a more elegant standards-based approach to the same solution appeared using JSON Web Tokens. Here is a good blog post explaining how to use them.
Most answers miss the point, which is to avoid having any server-side session. I don't want any application state in the server. I'll award the bounty to answer that came closest, but the real credit goes to the rest-discuss group and Jon Moore for the correct answer and to Mike Amundsen for helping me to actually understand it.
The best answer I've gotten is to use a cookie, but not the typical automatic session id cookie given to you by most application servers. The cookie (which will automatically be sent with each subsequent request) is a user identifier and time signed by the server. You can include an expiration time with the cookie so it simulates the typical 30 minute session on a server (which means you have to push it forward with subsequent requests) as well as keeps the same cookie from being valid forever.
The XHR/AJAX part is a red herring. This will work whether you are doing XHR requests or an old-fashioned page-by-page web application. The main points are:
The cookie is automatically sent on subsequent requests so there's no
special scripting required - it's just how browsers work already.
The server does not need to store any session for the user, so the user
can hit any server in a cluster and not have to re-authenticate.
Slightly interesting in that you consider pushing some of the authent to the client. If you want a conventional solution, KOGI's server-side suggestion is the way to go.
But you also seem to be asking questions about memory leaks involving your user supplied secrets. Good questions. But to take a general stab at answering that I'd say it would have to be browser specific. It's browser internals, javascript engine internals -dependent where a client side application (i.e., the browser, or js in the browser) is storing the values the user inputs.
Most likely those values are not replicated needlessly throughout memory, but there's no way to guarantee that. Apart from responsible javascript coding practices, there's nothing you can do to guarantee the limit of locations of user inputs.
Slight digression
The basic point is if you store it on the client it is not really secure -- unless, the serve stores encrypted information on the client with a key that only the server (or the user via their correct credentials), has. So you could conceivably code a JS application to do some authent on the client -- much the same as how bank card (used to?) do POS authent by checking the PIN to the PIN on the card, and not back at the DB. It's based on the (somewhat flimsy) assumption the user has no direct read/write access of the "dark area" cookie/local storage on client / mag strip on bank card. So I would only advise this as disqualifier for false authents and not as a sole qualifier for the credentials.
Main point
If you do want to be stateless, just store user credentials in localstorage, or as a cookie but encrypt them with a server key. When you need them send an XHR with the encrypted / use stored credentials to the server over HTTPS, let your server decrypt them and send them to the callback. Then pass those cleartext of HTTPS to do your authent.
Updated with clarifications
Hello,
When our users go to http://mysubdomain.server.com/login they get redirected to https://secure.server.com/login?subdomain=mysubdomain. So the actual login page is located on the secure.server.com subdomain.
The problem is that if the user logs in with the credentials meant for subdomainA and tells Firefox to remember the password, the browser will autocomplete the login form even if the user visits the login page meaning to log into subdomainB.
Firefox assumes that the login form on secure.server.com/login?subdomain=subdomainA is the same with the one on secure.server.com/login?subdomain=subdomainB.
At first, I thought Firefox remembers passwords based on a combination of the URL and the name attribute of the form, but I've tried changing the name based on the subdomain (name="login-<subdomain_name>"), and it still doesn't work.
How can I make Firefox remember passwords for subdomainA and for subdomainB separately, and not together?
I couldn't quite decipher what your setup is, but you can enable login manager debugging and check what Firefox does. You can also inspect signons.sqlite in your profile to see what pieces of data are stored with the login.
I thought that for web forms it keyed off the form's submit URL, but my memory is shady on this.
[edit]
source (nsLoginManager.js) says it only uses the form's action and the page's URL, and it uses not the action/page URL itself, but (see _getPasswordOrigin) the scheme+host+port combination.
If they're actually entering data into http just to be redirected to https after login, isn't that a bad scenario? You're already sending the most sensitive piece of data unencrypted across the wire.
I believe a better solution would be to redirect them to the https site and do login there...is there something I'm missing with your setup? Do they login again on the secure site?
AFAIK domain name (complete) is the current basis for remembering login. It wasn't always so, though. I'm not sure about protocol or port number, but a.domain.com is different from b.domain.com and domain.com, but same as a.domain.com/somewhere.
I have a website that I would like to allow both Forms and Windows Auth for. My problem is that it seems that when you setup IIS to allow both anonymous (Required for forms auth) and Windows auth that the browser won't send the user's network credentials.
It just uses the anonymous login. Is there any way either in IE8 or IIS to have it try Windows Auth 1st and then fall back to Anonymous?
Thanks for any help.
You can't ask for HTTP authentication (whether that's Basic Authentication or Integrated Windows Authentication) without causing the authentication dialogue box to pop in the case where there are no credentials yet.
So in general for hybrid HTTP-auth+cookie-auth approaches you enable both anonymous and authenticated access for the bulk of the site, but allow only authenticated access to one particular script.
When the user accesses a page without either kind of auth, you spit out a page with a login form for the cookie-based auth, and also a link to the one URL that allows only authenticated access. The user can fill out the form for cookies&forms auth, or hit the link to log in with HTTP auth instead.
If the user follows that link, they will be given a 401 response and must provide HTTP authentication, either through the auth dialog, or potentially automatically using integrated Windows authentication. Once this has happened once, the browser will start submitting the same credentials to every future page, so IIS will decode the credentials to give you the expected REMOTE_USER when your main site scripts are run.
Browsers will only submit the credentials to pages in the same directory as the 401 script, or subdirectories of this. For this reason it is best to put the HTTP-auth-required script in the root, for example as /login.aspx.
However, there are a few browsers that won't automatically submit credentials for further pages, and require every HTTP request to respond 401 first, before sending the request again with credentials. This makes optional-auth and hybrid-auth schemes impossible (as well as making browsing of protected sites much slower!). The only modern browser that does this is Safari. You may not care, as Safari's support for Integrated Windows Authentication has traditionally been shaky anyway, and it can still use the forms+cookies auth type.