LibreSSL 3.5 compatibility
LibreSSL is now closer to OpenSSL 1.1 than OpenSSL 1.0. According to https://undeadly.org/cgi?action=article;sid=20220116121253, this is the intention of OpenBSD developers.
According to #40630 (closed), many special cases are needed to compile Tor against LibreSSL 3.5 when using Tor's OpenSSL 1.0 compatibility mode, whereas only a small number of #defines are required when using OpenSSL 1.1 compatibility mode. One additional workaround is required for LibreSSL 3.4 compatibility.
Compiles and passes unit tests with LibreSSL 3.4.3 and 3.5.1.
Edited by Alex Xu