I have a (HTTPS) login.php page which remains HTTPS (ie once user logged in goes to account dashboard). Now the problem is say the user whilst logged on to the secure dashbo
Answered to help people who might stumble across this
As the the answer at Session lost when switching from HTTP to HTTPS in PHP has concluded, since you are using session.cookie_secure = 1 the cookie that contains the session ID is not transferred when the connection switches from HTTPS to HTTP. At HTTP connection, when you session_start(), PHP creates a new session id, which replaces the previous session id.
The answer also suggests a solution, pass the session id using query string, which is then picked up by the page. This smells of bad of security flaw. Don't forget the reason why we used HTTPS in the first place!
So the solution I suggest to you is that you redirect all http request to https counterparts. Use HTTPS for everything in your site, from css, images, to mundane static html pages. This is actually something that every application that is serious about security does. For example, visiting github page using HTTP will return:
HTTP/1.1 301 Moved Permanently
Server: nginx/0.7.67
Date: Sun, 08 May 2011 15:43:01 GMT
Content-Type: text/html
Content-Length: 185
Connection: close
Location: https://github.com/
301 Moved Permanently
301 Moved Permanently
nginx/0.7.67
Remember why you used HTTPS in the first place, if you want to be totally secure, use HTTPS for everything.
Detect if the request is HTTPS or not (See this question) at bootstrap.
If the request is HTTP, either redirect all requests to HTTPS home page, or you can try parsing $_SERVER['REQUEST_URI'] and redirecting HTTP request to their HTTPS counterpart using parse_url and http_build_url.
Second Alternative Solution
If you really really don't want to use HTTPS for everything, then don't session_start() on pages that are accessed with HTTP. Secure cookies will be retained when you do this.
Third Alternative Solution
The other solution is to try and detect the user by IP addresses and user agent. This is not guaranteed to be accurate, so what I suggest is just use HTTPS for everything. Paypal, for example, always use HTTPS even for mundane static pages.