Weird session scope issue in PHP - php

I am having a really unsual problem I have never had before, I have a signup page/form and a processing page that for submits to, on the processing page I set any errors that are in the user data like empty fields and set them to a session var array
$_SESSION['signup_errors'] = $signup_errors;
$signup_errors is an array that I set to the session, I can then access that session data on the same page but I just changed my site around to use mod-rewrite to change the URL's and the only thing that I can seem to think of is on my signup form I cannot access these session variables anymore and now that I use mod-rewrite the url is like this domain.com/account/new and it used to be domian.com/?p=account.new so now it appears that it is in a differnt folder, could that have something to do with it?
I have tried debugging it a lot and that is the only thing I can come up with is maybe because it appears to be a different directory now because of the mod-rewrite maybe that makes the session unaccessible?

Are you sure you're starting sessions on every page you're accessing? I would check to make sure there's
session_start();
Wherever necessary.
Also, what does
print_r( $_SESSION );
return? Anything at all? If not it would probably indicate what I was saying.

I would check that you're not changing domains. E.G. domain.com -> www.domain.com
Normally a cookie is used to track the session id, and by default, the cookie is tied to a single domain. I.E. If the session was created at www.domain.com, when you visited login.domain.com the cookie wouldn't be sent resulting in no session information.

It happened to me once, maybe you have a similar scenario. The session variable was temporary and I would destroy it once it was outputted to the screen.
With mod rewrite if you are routing everything, if there is a broken image, that might be redirected to your php script as well, it would in the back ground print out the error and destroy that session var.
Just a thought!

Related

$_SESSION, PHP, iframe, not getting the SESSION variables

I m creating a very simple PHP-based program for warehousing but quite complicated back-end process.
So here is the situation:
I have the login page that directs to authorization page where it set the session_name for the first time, session_start() and set the session variables.
After the authorization page, it goes to the main.php page that is a table with left hand side for menu (links) that I also did session_name() <-- same name as the one created from (1), and start the session.
On the right hand side of the main page is the iframe that display the page when user click the links on the left. I also did session_name() <-- same name as the one created from (1), and start the session.
Problem:
main.php is ok, it reads the session variable perfectly, but the iframe couldn't get the session variables (i tried to print_r($_SESSION), and came up empty). I tried var_dump(session_name("abc")), where "abc" is the session name that i used in (1), and it does show "abc", tried (isset($_SESSION)) and returns true... so I don't know what am I doing wrong...
EDIT:
I m sorry guys, i think i may have found the culprit... it is a logic error on my side... i have this condition to check every php page i created to destroy session when the user level is not authorized to use this current page. My bad.. thanks so much for your help guys!!
Make sure that session_start() is on all the pages:
session_start() creates a session or resumes the current one based on a session identifier passed via a GET or POST request, or passed via a cookie.
see PHP manual reference
To control the contents of the $_SESSION try to put in all ifreame pages the code:
<?php
session_start();
echo '<pre>';
var_dump($_SESSION);
echo '</pre>';
Did you use session_start() at the top of the page in both the iframe as well as main.php?
You need to put session_start() on the top of the iframe too.
This might solve your problem: php session & iframe
Additionally: Nothing is simple if you're using iframes to display large portions of your webiste. You might want to consider not using them.
I had the same problem with multiple iframes on one of my PHP webpages.
In my case, some AJAX calls to PHP endpoints were being made to www.example.com when the page was loaded using http://example.com. If you are NOT consistent with the domain path, you may have session issues since a request from www.example.com is technically from a subdomain as oppose to being made directly from http://example.com. You can avoid this problem altogether by always using relative paths to your PHP based API when making AJAX calls in JavaScript.
I found this was the case by inspecting my cookies in Chrome. I noticed two different cookies with a different PHP session ID in them. One was set for www.example.com while the other was set for example.com
As mentioned in some of the other answers, you can always set the session cookie domain to work on all of your subdomains along with your main site by using the following:
ini_set("session.cookie_domain", ".domain.com");
PHP by default will set a new session per domain / subdomain. Hope this helps!

PHP + Logout Member when Session Expires

I've a site where people login and a SESSION is created.
I have noticed that if you leave the site for long enough (not sure exact time frame) the session ends but the members is still in the site. They can still click and navigate around and I believe this has resulted in some meaningless data in the DB as SESSION variables like userID don't exist.
I was looking for advice around logging users out when the SESSION ends.
I have looked at code like this - any better ideas?
<?php if(!isset($_SESSION[]) {header(loginpage.php);}?>
Is there a better way to write the above code?
Where should this code be placed? Just on the navigation menu or really on any place a user can click?
Finally is there a way to understand when the SESSION naturally expires - is there a SESSION variable I can print to screen to see the timeleft etc?
thanks
You need to validate the session, you already headed into that direction with your code, but it's not enough:
<?php if(!isset($_SESSION[]) {header(loginpage.php);}?>
It's not enough because $_SESSION[] exists automatically after the session is started (the session mechanism in PHP, see session_start).
Instead, if you have saved the userID inside the session, check that one:
isset($_SESSION['userID'])
If the session really expired, it should not be set.
I agree with the above answer. I would say it depends on how your application is architected to say where this belongs. before there is any output to the screen I am assuming your calling session_start, then immediately check for a session variable such as userID that gets set after a user logs in. if it's not set redirect setting a header for location to your login page. you could also write some js that checks the session cookie for a value at a specified interval(I believe, it's been a while so test it out), then when the variable isn't present you can redirect to the login page. a third way would be for the js code to make an XHR call to a php script to check out the session for you.

Losing session variables after redirect

User fills in username and password.
If it's correct, the page loads some information such as user_id to a session variable.
The script makes a header('Location') redirect.
Somehow the next page doesn't recognize the session... how come?
The redirection is to the same domain, and all pages have session_start();
And I found it more likely to happen in IE than in FF... strange.
Is it possible that cookies aren't enabled?
In order to be able to associate session variables with a specific client instance (ie. how session variables can be used on your browser and my browser at the same time without getting into a conflict), a "session ID" (or "SID") is generated per session. This ID is stored on the server, as well as on the client, usually in the form of a cookie. However, if cookies are not enabled, the session ID is passed along as part of the query string of the URL in each request so that the server can know what session ID belongs to the client.
When you redirect by a header() call, PHP does not automatically insert the SID into the new request, so you will need to append it yourself, in the form of:
header("Location: my_url.com/my_page.php?" . SID)
where SID is a constant defined by PHP that contains the necessary part of the query string (equivalent to session_name() . '=' . session_id(), if a session ID exists).
See Passing the Session ID for more details.
I just had a similar issue, the solution was to simply add an exit(); instruction under the header(..) redirection.
Two thoughts:
Is session_start() located at the top of the scripts, before anything is sent to the browser?
Is the domain exactly the same? www.mydomain.com re-directing to mydomain.com would lead to the problem you describe.
header("Location: my_url.com/my_page.php?" . SID)
exit();
It only worked after I added exit() below the header();
The WordPress documentation states that cookies will be cleared if the user's password is changed. That will kill the session, regardless of whether a redirect happens. So long as you can prevent the cookies from being cleared (and an exit() may do that, as suggested in other answers) than the session should remain.
Note: If current user's password is being updated, then the cookies
will be cleared!
http://codex.wordpress.org/Function_Reference/wp_update_user
I had this problem today and have been searching for a way to fix it. I already had what everyone else has mentioned and could not find an answer anywhere.
Eventually I found the answer after watching my session variables with Firebug. I noticed that on the pages that the variables were being lost, the session Parameter:secure was being set to true for some reason unknown to me.
The fix was to set the secure parameter to false before the session was created.
I accomplished this using session_set_cookie_params. Something like this:
session_set_cookie_params([lifetime], [path], [domain], false, true);

problem with sessions and redirection php

Im setting a session variable on hypothetical page number 1. The user then clicks a link to go to a site off the server, and then comes back to page number 1. Problem is, the session variables i set on page one, are no longer set when the user comes back.
Is this a known issue with php, is there any work around?
I am starting the session on the page, and i am echoing the session variables after i set them to make sure they set and they are.
Not sure where to go with this.
Are you sure you call session_start() in all the scripts that use the session variables?
it is possible that the session timeout has expired when the user comes back .. also i think the session has a feature to check for referrers , so u can check that too .. also make sure when the user comes back he lands on the exact same domain
You need to store the session ID in a cookie, and then read that cookie when the user comes back.

PHP Session not working in PHP5

I have 2 pages: login.php and index.php. Both pages start with
session_start();
When I set
$_SESSION['user'] = "name";
in login.php and than open index.php, my session object is empty. How come?
EDIT:
I found the problem: IE 7. I had to grand access to my domain. However, I thought a session is stored on the server, instead of the client? Than why do I have IE grand access to my domain? (http://www.pcwindowstips.com/2007/09/04/how-to-enable-cookies-in-internet-explorer-7/)
I thought a session is stored on the server, instead of the client? Than why do I have IE grant access to my domain? (http://www.pcwindowstips.com/2007/09/04/how-to-enable-cookies-in-internet-explorer-7/)
The way sessions work is that a session cookie is stored for the site, which contains your session ID. The only way the server knows who you are is when it reads the session ID cookie on every page load. All of the $_SESSION data is stored on the server for each user, but the cookie must be set for the server to know which $_SESSION data to retrieve.
This is also why you can essentially "become" another user if you obtain their session id cookie.
Internet Explorers have a stricter cookie policy than most other browsers. Check your session cookie parameters (see also session_get_cookie_params()) and try to replace the default values by explicit values where possible. Additionally you might send a [fake P3P policy](http://msdn.microsoft.com/en-us/library/ms537343(VS.85).aspx) to satisfy the Internet Explorers.
Perhaps this variable in php.ini is mapping to an existing path
session.save_path = "c:/wrong/path"
Here is something that happened to me that might shed light for someone. My session wasn't working properly. IE 8 and Firefox were losing the session information.
I included a file. That included file had an extra carriage return after the trailing &ques?>
That carriage return started the session. I put session_start after the include. BOOM.
Not much info here, I'll try to use my psychic powers.
After the user logs in, do you set the session var and then redirect the user to index.php using an http header? If so, I don't think the session cookie gets sent to the user. If that is the case, the solutions are:
call session_start() when the login form is initially displayed (not just after the user posts back to it); or:
display a "login successful!" message and then redirect with a meta-refresh, or just provide a link to index.php.
You can also try to dump the session ID on both pages, to see if you are somehow starting a new session:
echo 'Session ID is: ' . SID . "<br/>\n"
You need verify if the cookies are enabled and nothing ( this includes blank lines in the beginning or in the end of archive) sent to browser before you call session_start().

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