How does Tor network handle individual sessions?

Question

I mean, if I request some site, it goes through big chain of proxies, but how the proxies know where to send it?

I think that it works like : I say get google to proxy 1 -> proxy one tells to get google to proxy 2 -> proxy 2 [and so on] And on the way back it is reversed. The last proxy knows which proxy ordered the website so it sends it to this and so on. But this seems to me a bit incomplete if it's how it really works.

Am I missing something or am I completely wrong ?

Answer 1

Brief overview:

First, you get a circuit of Tor nodes, let's say 1, 2, 3.

Next, you craft an encrypted packet to node 3, encrypt that in a packet to node 2, then encrypt that in a packet to node 1.

This way, node 1 only knows the next hop is node 2, node 2 only knows the next hop is node 3, and node 3 knows the final destination. Also, 3 only knows about node 2, node 2 only knows about node 1, etc. Node 1 doesn't know the destination and node 3 doesn't know the origin.