Rewrite exit scanner to produce exit lists according to new format
The current exit scanner is purpose written software using Haskell. It is non-trivial to update this program to run on a modern Debian system and would be easier in the longer term to simply replace.
This task requires the new exit list specification to be completed in legacy/trac#29624 (moved).
Expected new features:
- Written in Python
- Support for IPv6
- Support for new exit list format
Features we would like:
- Cryptographically signed measurement results
- Archival signatures