Is there a session variable?

Is there a way to access a session variable for the url in reporting services? This is hard to explain, but our internal users access our website and view reports via one url, while external users use a different url to view the website and reports. I used the jump to url in some of my reports, but I need the report to read which url they came in on so that it can jump to the correct url that I need it to. Has anyone done anything similar to this?Anyone have any ideas? I use "jump to url" in quite a few of our reports w/ the link that it is jumping to being different information on our website. Our internal users see our website on a different url than our external users, so in my jump to link I need to conditionally set whether they go to the one url or the other, but I have to determine how they came in to begin with to determine which one they jump to.