I'm developing webpage (let's call it NWP) which should co-work with joomla (1.5) webpage. user db is shared and accessible for both web-pages. also these 2 sites are served on sub domains.
when user authenticates on NWP, I update session table of the joomla with my session_id and provide each parameter which are required. after this I also change cookie on the joomla webpage (session cookie with already created session id in joomla db).
after this job is done. Joomla should recognize me as logged in, but nothing really happens. I think joomla itself, generates "some kind" of session_id to identify that it's not faked, as mine.
Please, help me or share your experience for my goal. You would help me very much!
It would be very unwise to give an answer based on your question.
Joomla 1.5 is now very old, not supported, and likely riddled with holes. 3.6 is the latest version, almost nothing else is currently supported.
There have been several very serious security flaws found in the last 6-12 months. They will not have been fixed in 1.5