exclude_badExits/README.md

This extends nusenu's basic idea of using the stem library to
dynamically exclude nodes that are likely to be bad by putting them
on the ExcludeNodes or ExcludeExitNodes setting of a running Tor.
* https://github.com/nusenu/noContactInfo_Exit_Excluder
* https://github.com/TheSmashy/TorExitRelayExclude

The basic cut is to exclude Exit nodes that do not have a contact.
That can be extended to nodes that do not have an email in the contact etc.

But there's a problem, and your Tor notice.log will tell you about it:
you could exclude the nodes needed to access hidden services or
directorues. So we need to add to the process the concept of a whitelist.
In addition, we may have our own blacklist of nodes we want to exclude,
or use these lists for other applications like selektor.

So we make two files that are structured in YAML:
```
/etc/tor/yaml/torrc-goodnodes.yaml
GoodNodes:
  Relays:
    IntroductionPoints:
      - NODEFINGERPRINT
  ...
By default all sections of the goodnodes.yaml are used as a whitelist.

/etc/tor/yaml/torrc-badnodes.yaml
BadNodes:
  ExcludeExitNodes:
    BadExit:
      # $0000000000000000000000000000000000000007
```
That part requires [PyYAML](https://pyyaml.org/wiki/PyYAML)
https://github.com/yaml/pyyaml/

Right now only the ExcludeExitNodes section is used by we may add ExcludeNodes
later, and by default all sub-sections of the badnodes.yaml are used as a
ExcludeExitNodes but it can be customized with the lWanted commandline arg.

The original idea has also been extended to add different conditions for
exclusion: the ```--contact``` commandline arg is a comma sep list of conditions:
* Empty - no contact info
* NoEmail - no @ sign in the contact',
More may be added later.

Because you don't want to exclude the introduction points to any onion
you want to connect to, ```--white_onions``` should whitelist the
introduction points to a  comma sep list of onions, but is
currently broken in stem 1.8.0: see:
* https://github.com/torproject/stem/issues/96
* https://gitlab.torproject.org/legacy/trac/-/issues/25417

```--torrc_output``` will write the torrc ExcludeNodes configuration to a file.

Now for the final part: we lookup the Contact info of every server
that is currently in our Tor, and check it for its existence.
If it fails to provide the well-know url, we assume its a bogus
relay and add it to a list of nodes that goes on ExcludeNodes -
not just exclude Exit.

If the Contact info is good we add the list of fingerprints to add
to ExitNodes, a whitelist of relays to use as exits.

```--proof_output``` will write the contact info as a ciiss dictionary
to a YAML file. If the proof is uri-rsa, the well-known file of fingerprints
is downloaded and the fingerprints are added on a 'fps' field we create
of that fingerprint's entry of the YAML dictionary. This file is read at the
beginning of the program to start with a trust database, and only new
contact info from new relays are added to the dictionary.

You can expect it to take an hour or two the first time this is run:
>700 domains.

For usage, do ```python3 exclude_badExits.py --help`

## Usage
```
usage: exclude_badExits.py [-h] [--https_cafile HTTPS_CAFILE]
                           [--proxy_host PROXY_HOST] [--proxy_port PROXY_PORT]
                           [--proxy_ctl PROXY_CTL] [--torrc TORRC]
                           [--timeout TIMEOUT] [--good_nodes GOOD_NODES]
                           [--bad_nodes BAD_NODES] [--contact CONTACT]
                           [--bad_contacts BAD_CONTACTS]
                           [--strict_nodes {0,1}] [--wait_boot WAIT_BOOT]
                           [--points_timeout POINTS_TIMEOUT]
                           [--log_level LOG_LEVEL]
                           [--bad_sections BAD_SECTIONS]
                           [--white_services WHITE_SERVICES]
                           [--torrc_output TORRC_OUTPUT]
                           [--proof_output PROOF_OUTPUT]
```

### Optional arguments:

```
  -h, --help            show this help message and exit
  --https_cafile HTTPS_CAFILE
                        Certificate Authority file (in PEM)
```
```
  --proxy_host PROXY_HOST, --proxy-host PROXY_HOST
                        proxy host
  --proxy_port PROXY_PORT, --proxy-port PROXY_PORT
                        proxy control port
  --proxy_ctl PROXY_CTL, --proxy-ctl PROXY_CTL
                        control socket - or port
```
```
  --torrc TORRC         torrc to check for suggestions
  --timeout TIMEOUT     proxy download connect timeout
```
```
  --good_nodes GOOD_NODES
                        Yaml file of good info that should not be excluded
  --bad_nodes BAD_NODES
                        Yaml file of bad nodes that should also be excluded
```
```
  --contact CONTACT     comma sep list of conditions - Empty,NoEmail
  --bad_contacts BAD_CONTACTS
                        Yaml file of bad contacts that bad FPs are using
```
```
  --strict_nodes {0,1}  Set StrictNodes: 1 is less anonymous but more secure,
                        although some sites may be unreachable
  --wait_boot WAIT_BOOT
                        Seconds to wait for Tor to booststrap
  --points_timeout POINTS_TIMEOUT
                        Timeout for getting introduction points - must be long
                        >120sec. 0 means disabled looking for IPs
```
```
  --log_level LOG_LEVEL
                        10=debug 20=info 30=warn 40=error
  --bad_sections BAD_SECTIONS
                        sections of the badnodes.yaml to use, comma separated,
                        '' BROKEN
```
```
  --white_services WHITE_SERVICES
                        comma sep. list of onions to whitelist their
                        introduction points - BROKEN
```
```
  --torrc_output TORRC_OUTPUT
                        Write the torrc configuration to a file
  --proof_output PROOF_OUTPUT
                        Write the proof data of the included nodes to a YAML
                        file
```