On many places we've been assuming that there's only a single worker,
but we still often didn't utilize the property well.  To get the pointer
we used various ways, all even untyped:
 - __worker global variable in lua
 - uv_default_loop()->data
 - kr_request::daemon_context

Now we instead simply define a global typed pointer the_worker.

Nitpick: also worker_{init,deinit}() are reordered to correspond
to the order of the fields, etc.

There's no support for the "dns" and "tls" kinds (for now).

Tested briefly:
> modules = { 'http' }
> net.listen('/tmp/kresd-socket', nil, { kind = 'webmgmt' })
$ socat TCP-LISTEN:5555,reuseaddr,fork UNIX-CLIENT:/tmp/kresd-socket
$ xdg-open http://127.0.0.1:5555

http DoH: make answers include access-control-allow-origin: *

See merge request !823

Vladimír Čunát authored 5 years ago and Tomas Krizek committed 5 years ago

Otherwise most browsers won't allow JS from *other* sites to use the
data - one of the two primary use cases for DoH as stated in RFC 8484.

This is yet another logically equivalent change after 270d9964.
Now it's written in a way that expresses the original intention more
clearly and without copy&paste or long lines.

It seems easiest to verify by inspecting the meaning of the code
*separartely* for the two cases, based on condition:
cur_addr_score < KR_NS_TIMEOUT

daemon TCP to upstream: don't send wrong message length

See merge request !816

See the added comments.  Such bugs are tricky, because the old code
would typically work just fine, only if libuv/OS decided to postpone
copying the data (perhaps large load), we would send two bytes from
this address on C stack - their later value (hard to predict what).

Security risks: the two bytes might theoretically contain information
that was more or less private and we just send it to some DNS server
(possibly over unencrypted TCP), but ATM I find it very unlikely that
this bug could be practically exploited.

clarification to docs for net.bufsize()

See merge request !821

modules/ta_update.test: increase test times for CI

See merge request !822

docs fixes

See merge request !814

- generate most of it from source
- make order the same in implementation and description