Make tor_tls_get_buffer_sizes() work again
Where supported, Tor uses OpenSSL skulduggery to find out how much RAM openssl has allocated and/or is using for buffers in each SSL object, and . This information is only used for logging right now (in
dumpstats()), but it has potential use in our OOM/DOS prevention code.
The tricks that we used up till now no longer actually work with OpenSSL 1.1.0, however, since the relevant structures are now opaque. We'll either need to find another way to get their sizes, or add some API to OpenSSL to expose them.
This is low-priority, unless we actually have time to use this information in OOM calculation.