- allow to specify when they are wanted on starting a resolve
- match dns cache entries accordingly. An entry which never
tried to get HTTPS-RRs is no answer for a resolve that wants
it.
- fix late arrivals of resolve answers to match the "async"
records that started them - if it still exists.
- provide for multiple "async" resolves in a transfer at the
same time. We may need to resolve an IP interface while the
main connection resolve has not finished yet.
- allow lookup of HTTPS-RR information as soon as it is
available, even if A/AAAA queries are still ongoing.
For this, the "async" infrastructure is changed:
- Defined bits for DNS queries `CURL_DNSQ_A`, `CURL_DNSQ_AAAA`
and `CURL_DNSQ_HTTPS`. These replace `ip_version` which says
nothing about HTTPS.
Use them in dns cache entries for matching.
- enhance the `async->id` to be a unique `uint32_t` for
resolves inside one multi. This is weak, as the id may
wrap around. However it is combined with the `mid` of
the easy handle, making collisions highly unlikely.
`data->state.async` is only accessed in few places where
the mid/async-id match is performed.
- vtls: for ECH supporting TLS backends (openssl, rustls, wolfssl),
retrieve the HTTPS-RR information from the dns connection filter.
Delay the connect if the HTTPS-RR is needed, but has not
been resolved yet.
The implementation of all this is complete for the threaded
resolver. c-ares resolver and DoH do not take advantage of
all new async features yet. To be done in separate PRs.
Details:
c-ares: cleanup settings and initialisation. Any ares channel
is only being created on starting a resolve and propagating
operations in setopt.c to the channel are not helpful.
Changed threaded+ares pollset handling so that they do not
overwrite each others `ASYNC_NAME` timeouts.
Add trace name 'threads' for tracing thread queue and
pool used by threaded resolver.
Closes#21175
- asyn-thrdd.c: scope an include.
- apply more clang-format suggestions.
- tidy-up PP guard comments.
- delete empty line from the top of headers.
- add empty line after `curl_setup.h` include where missing.
- fix indent.
- CODE_STYLE.md: add `strcpy`.
Follow-up to 8636ad55df#20088
- lib1901.c: drop unnecessary line.
Follow-up to 436e67f65b#20076Closes#20070
When the target host is on a different port than 443, the name
"_[port]._https.[name]" shall be used.
Fixes#19301
Reported-by: Gunni on github
Closes#19324
"asyn" is the internal name under which both c-ares and threaded
resolver operate. Make the naming more consistent. Implement the c-ares
resolver in `asyn-ares.*` and the threaded resolver in `asyn-thrdd.*`.
The common functions are in `asyn-base.c`.
When `CURLRES_ASYNCH` is defined, either of the two is used and
`data->state.async` exists. Members of that struct vary for the selected
implementation, but have the fields `hostname`, `port` and `ip_version`
always present. This are populated when the async resolving starts and
eliminate the need to pass them again when checking on the status and
processing the results of the resolving.
Add a `Curl_resolv_blocking()` to `hostip.h` that relieves FTP and SOCKS
from having to repeat the same code.
`Curl_resolv_check()` remains the function to check for status of
ongoing resolving. Now it also performs internally the check if the
needed DNS entry exists in the dnscache and if so, aborts the asnyc
operation. (libcurl right now does not check for duplicate resolve
attempts. an area for future improvements).
The number of functions in `asyn.h` has been reduced. There were subtle
difference in "cancel()" and "kill()" calls, both replaced by
`Curl_async_shutdown()` now. This changes behaviour for threaded
resolver insofar as the resolving thread is now always joined unless
`data->set.quick_exit` is set. Before this was only done on some code
paths. A future improvement would be a thread pool that keeps a limit
and also could handle joins more gracefully.
DoH, not previously tagged under "asny", has its struct `doh_probes` now
also in `data->state.async`, moved there from `data->req` because it
makes more sense. Further integration of DoH underneath the "asyn"
umbrella seems like a good idea.
Closes#16963
Made the HTTPS-RR parser a little stricter while at it.
Drop the ALPN escape handling, that was not needed.
Make the hode handle (and ignore) duplicate ALPN entries.
Closes#16972
- fold DoH and async HTTPS-RR handling into common code.
have common cleanups, etc. Have a CURLcode result in async
handling to allow HTTPS RR parsing to fail.
- keep target, ipv4hints, ipv6hints, port and echconfig also
when resolving via cares. We need to know `target` and `port`
when evaluating possible ALPN candidates to not go astray.
- add CURL_TRC_DNS for tracing DNS operations
- replace DoH specific tracing with DNS, use doh as alias
for dns in curl_global_tracea()
Closes#16132
Allow building with c-ares and yet use threaded resolver for the main
host A/AAAA resolving:
`--with-ares` provides the c-ares install path and defaults to use
c-ares for name resolving
`--with-threaded-resolver` still uses c-ares in the build (for HTTPS)
but uses the threaded resolver for "normal" resolves.
It works similarly for cmake: ENABLE_ARES enables ares, and if
ENABLE_THREADED_RESOLVER also is set, c-ares is used for HTTPS RR and
the threaded resolver for "normal" resolves.
HTTPSRR and c-ares-rr are new features return by curl_version_info() and
thus shown by curl -V.
The c-ares-rr feature bit is there to make it possible to distinguish
between builds using c-ares for all name resolves and builds that use
the threaded resolves for the regular name resolves and c-ares for
HTTPSRR only. "c-ares-rr" means it does not use c-ares for "plain" name
resolves.
HTTPSRR support is EXPERIMENTAL only.
Closes#16054
