Stop modifying addr on connections, and delete real_addr
In connection_or_check_canonicity(), we overwrite conn.addr with the canonical address of the relay in the consensus. That makes accurate logging impossible.
And so we also need channel.real_addr, to store the actual address of the remote peer. And for some reason, we also have conn.address, a string copy of the peer's canonical address and port.
This is... a mess.
Here's the high-level interface I'd like to see:
- use a function to format a connection or channel addresses for loogging
- use exactly as many address and port variables as needed in connection and channel (no extras!)
- qualify each address and port variable's name with its purpose
For example, here's one possible design:
- delete addr, port, address, and real_addr
- add remote_ap, a tor_addr_port_t that is the remote address and port of the TCP connection to the remote peer
- implement connection_describe(), which:
- formats remote_ap,
- formats is_canonical (and any other useful info), and
- calls node_describe() to format the canonical IPv4 and IPv6 addresses and ports of the remote peer.
We may also need separate fields for reverse proxied addresses, see the comment at: https://github.com/torproject/tor/blob/7517e1b5d31aada1f594c2594737a231d9d8e116/src/core/or/channeltls.c#L1339
If we need separate variables or functions for channels, we can use a similar design. (But ideally, re-using as many functions and variables as possible.)
This is important for Sponsor 55: getting accurate connection information will make diagnosing bugs much easier.