c68e3d2c57 doc: add release notes for Tor PoW defenses (Vasil Dimov)
4bae84c94a doc: add a hint to enable PoW defenses to manual hidden services (Vasil Dimov)
4c6798a3d3 tor: enable PoW defenses for automatically created hidden services (Vasil Dimov)
fb993f7604 tor, fuzz: reuse constants instead of duplicating (Vasil Dimov)
Pull request description:
Enable [PoW defenses](https://tpo.pages.torproject.net/onion-services/ecosystem/technology/security/pow/) for hidden services that we create via Tor Control using the [`ADD_ONION` command](https://spec.torproject.org/control-spec/commands.html#add_onion).
The ability to do that has been added in [tor-0.4.9.2-alpha](02c1804446). Previous versions return a syntax error to the `ADD_ONION` command with `PoWDefensesEnabled=1`, so the approach here is to try with PoW and if we get syntax error, then retry without PoW.
Also update `doc/tor.md` with a hint on enabling PoW on manually configured Tor hidden services.
ACKs for top commit:
willcl-ark:
ACK c68e3d2c57
fjahr:
tACK c68e3d2c57
sedited:
ACK c68e3d2c57
Tree-SHA512: 56f57bc770b89389c35a4c0bc2a28804d17b1479ecd4d9b764695d6c9d2994425aee759e71658d7b57088bbe43ce90b94fb972f66d79ef903e0c1a4d6c4562f3