Add Socks v5 support to daemon and wallet

[vtnerd]

Socks v5 adds IPv6 support and basic username/password authentication. The user/pass authentication is a cheap way to prevent rogue applications from requesting proxied connections. Tor and SSH do not support authentication but I2P, Nym, and Dante do.

When I started this implementation, I didn't know Nym added Socks v4 support. This makes the patch somewhat less useful, as the original #8562 Socks v5 request was for Nym support. This patch might want to be rejected on that reason alone - the only useful features are user/pass and IPv6.

This includes a fairly extensive explanation of proxies in the daemon and cli wallets, so that might be useful for keeping regardless.

[vtnerd]

Crap, looks like older versions of boost don't have some ASIO functionality I used. Crap, will have to update.

[tobtoht]

What would be the minimum Boost version for this PR?

Is it time to undust #9162 and bump the minimum Boost requirement?

[vtnerd]

The minimum version for this feature would be 1.67. In this case, its not really critical, I should be able to work-around it.

[iamamyth]

After many years, IPv6 has started to see substantial, and increasing, adoption, so I think this would be a reasonable addition. However, it's not urgent, and, based on the comments in #9162, I think you could safely assume Boost 1.67 (Ubuntu 18.04 continues to wither) and roll out this feature after a boost version upgrade to 1.67. Of course, you can do the extra work to support the current Boost version, but you may very well have better uses for your time.

[vtnerd]

I just pushed a change to fix the Boost issues. Everything looks good for that.

The functional tests failed, but it looks spurious right now. Testing locally to confirm, and may just push a dummy update to re-run the tests.

[vtnerd]

Good for review!

[sneurlax]

Adds SOCKSv5 support with tests and documentation included. Tested working. The code looks relatively minimal such that I don't see anything to remove, really. I don't see any potential privacy or security concerns, LGTM

[sneurlax]

Closes #9443

[woodser]

Closes #9390 ?

[woodser]

This PR needs rebased, and hopefully moves forward. Will be nice to support IPv6.

[vtnerd]

Force Push:

• To newest version of master, with changes along the way to resolve conflicts
• Changes requested by @nahuhh

[vtnerd]

Force pushed a size check fix.

[SyntheticBird45]

Tested, no issues.

[nahuhh]

@vtnerd would it make sense to revert this change, since boost on master and release has been updated to 1.67+?

https://github.com/monero-project/monero/compare/9a9d2064290ac9f8f8137053341efe2ee3412a2a..f3fcac82acbbf35cc9c23a1cc0e6c36620ab194e

[vtnerd]

Yes, looks like this is no longer needed, so I will try to revert that change.

[vtnerd]

Force pushed a change to revert the workaround for older Boost versions. I'm not sure if this is a good idea, as officially the last supported version is Boost 1.66

@selsta , what do you think?

[vtnerd]

Nevermind, I just checked again and this code should work with Boost 1.66+ so everything should be good.

[nahuhh]

Force pushed a change to revert the workaround for older Boost versions. I'm not sure if this is a good idea, as officially the last supported version is Boost 1.66

@selsta , what do you think?

Also, i think we're raising min to 1.69
#9807 (comment)

[selsta]

@nahuhh we will use 1.69 for release binaries but ideally work around the boost bug so we can keep a lower minimum

[vtnerd]

I just verified this still compiles with Boost 1.66-1.87, so no issues with that.