curl/docs
Stefan Eissing 671158242d
connections: introduce http/3 happy eyeballs
New cfilter HTTP-CONNECT for h3/h2/http1.1 eyeballing.
- filter is installed when `--http3` in the tool is used (or
  the equivalent CURLOPT_ done in the library)
- starts a QUIC/HTTP/3 connect right away. Should that not
  succeed after 100ms (subject to change), a parallel attempt
  is started for HTTP/2 and HTTP/1.1 via TCP
- both attempts are subject to IPv6/IPv4 eyeballing, same
  as happens for other connections
- tie timeout to the ip-version HAPPY_EYEBALLS_TIMEOUT
- use a `soft` timeout at half the value. When the soft timeout
  expires, the HTTPS-CONNECT filter checks if the QUIC filter
  has received any data from the server. If not, it will start
  the HTTP/2 attempt.

HTTP/3(ngtcp2) improvements.
- setting call_data in all cfilter calls similar to http/2 and vtls filters
  for use in callback where no stream data is available.
- returning CURLE_PARTIAL_FILE for prematurely terminated transfers
- enabling pytest test_05 for h3
- shifting functionality to "connect" UDP sockets from ngtcp2
  implementation into the udp socket cfilter. Because unconnected
  UDP sockets are weird. For example they error when adding to a
  pollset.

HTTP/3(quiche) improvements.
- fixed upload bug in quiche implementation, now passes 251 and pytest
- error codes on stream RESET
- improved debug logs
- handling of DRAIN during connect
- limiting pending event queue

HTTP/2 cfilter improvements.
- use LOG_CF macros for dynamic logging in debug build
- fix CURLcode on RST streams to be CURLE_PARTIAL_FILE
- enable pytest test_05 for h2
- fix upload pytests and improve parallel transfer performance.

GOAWAY handling for ngtcp2/quiche
- during connect, when the remote server refuses to accept new connections
  and closes immediately (so the local conn goes into DRAIN phase), the
  connection is torn down and a another attempt is made after a short grace
  period.
  This is the behaviour observed with nghttpx when we tell it to  shut
  down gracefully. Tested in pytest test_03_02.

TLS improvements
- ALPN selection for SSL/SSL-PROXY filters in one vtls set of functions, replaces
  copy of logic in all tls backends.
- standardized the infof logging of offered ALPNs
- ALPN negotiated: have common function for all backends that sets alpn proprty
  and connection related things based on the negotiated protocol (or lack thereof).

- new tests/tests-httpd/scorecard.py for testing h3/h2 protocol implementation.
  Invoke:
    python3 tests/tests-httpd/scorecard.py --help
  for usage.

Improvements on gathering connect statistics and socket access.
- new CF_CTRL_CONN_REPORT_STATS cfilter control for having cfilters
  report connection statistics. This is triggered when the connection
  has completely connected.
- new void Curl_pgrsTimeWas(..) method to report a timer update with
  a timestamp of when it happend. This allows for updating timers
  "later", e.g. a connect statistic after full connectivity has been
  reached.
- in case of HTTP eyeballing, the previous changes will update
  statistics only from the filter chain that "won" the eyeballing.
- new cfilter query CF_QUERY_SOCKET for retrieving the socket used
  by a filter chain.
  Added methods Curl_conn_cf_get_socket() and Curl_conn_get_socket()
  for convenient use of this query.
- Change VTLS backend to query their sub-filters for the socket when
  checks during the handshake are made.

HTTP/3 documentation on how https eyeballing works.

TLS improvements
- ALPN selection for SSL/SSL-PROXY filters in one vtls set of functions, replaces
  copy of logic in all tls backends.
- standardized the infof logging of offered ALPNs
- ALPN negotiated: have common function for all backends that sets alpn proprty
  and connection related things based on the negotiated protocol (or lack thereof).

Scorecard with Caddy.
- configure can be run with `--with-test-caddy=path` to specify which caddy to use for testing
- tests/tests-httpd/scorecard.py now measures download speeds with caddy

pytest improvements
- adding Makfile to clean gen dir
- adding nghttpx rundir creation on start
- checking httpd version 2.4.55 for test_05 cases where it is needed. Skipping with message if too old.
- catch exception when checking for caddy existance on system.

Closes #10349
2023-02-02 09:57:34 +01:00
..
cmdline-opts write-out.d: add 'since version' to %{header_json} documentation 2023-02-02 08:31:41 +01:00
examples connections: introduce http/3 happy eyeballs 2023-02-02 09:57:34 +01:00
libcurl curl_free.3: fix return type of curl_free 2023-01-31 08:32:37 +01:00
.gitignore copyright: update all copyright lines and remove year ranges 2023-01-03 09:19:21 +01:00
ALTSVC.md docs: minor grammar fixes 2022-09-29 10:44:12 +02:00
BINDINGS.md docs: update sourceforge project links [ci skip] 2022-10-01 18:40:47 +00:00
BUFREF.md docs: spellfixes 2022-09-21 15:20:08 +02:00
BUG-BOUNTY.md BUG-BOUNTY.md: mention the audit exception 2022-05-19 11:14:54 +02:00
BUGS.md docs: minor grammar fixes 2022-09-29 10:44:12 +02:00
CHECKSRC.md docs: spellfixes 2022-09-21 15:20:08 +02:00
CIPHERS.md docs: spellfixes 2022-09-21 15:20:08 +02:00
CMakeLists.txt copyright: update all copyright lines and remove year ranges 2023-01-03 09:19:21 +01:00
CODE_OF_CONDUCT.md
CODE_REVIEW.md docs: spellfixes 2022-09-21 15:20:08 +02:00
CODE_STYLE.md scripts: move three scripts from lib/ to scripts/ 2022-03-23 15:26:11 +01:00
CONNECTION-FILTERS.md lib: connection filters (cfilter) addition to curl: 2022-11-11 15:17:51 +01:00
CONTRIBUTE.md misc: typo and grammar fixes 2022-10-27 10:01:30 +02:00
curl-config.1 copyright: update all copyright lines and remove year ranges 2023-01-03 09:19:21 +01:00
CURL-DISABLE.md docs: spellfixes 2022-09-21 15:20:08 +02:00
DEPRECATE.md noproxy: support for space-separated names is deprecated 2023-01-04 09:15:37 +01:00
DYNBUF.md docs: spellfixes 2022-09-21 15:20:08 +02:00
EARLY-RELEASE.md docs/EARLY-RELEASE.md: how to determine an early release 2022-11-05 23:52:11 +01:00
EXPERIMENTAL.md openssl: Don't ignore CA paths when using Windows CA store (redux) 2023-01-17 03:32:58 -05:00
FAQ docs: spelling nits 2022-09-29 21:29:04 +00:00
FEATURES.md docs: spellfixes 2022-09-21 15:20:08 +02:00
GOVERNANCE.md misc: typo and grammar fixes 2022-10-27 10:01:30 +02:00
HELP-US.md docs: add link to GitHub Discussions 2023-01-02 00:26:37 +01:00
HISTORY.md docs: spellfixes 2022-09-21 15:20:08 +02:00
HSTS.md docs: spellfixes 2022-09-21 15:20:08 +02:00
HTTP2.md docs: spellfixes 2022-09-21 15:20:08 +02:00
HTTP3.md connections: introduce http/3 happy eyeballs 2023-02-02 09:57:34 +01:00
HTTP-COOKIES.md HTTP-COOKIES.md: update the 6265bis link to draft-11 2022-11-18 09:59:33 +01:00
HYPER.md misc: typo and grammar fixes 2022-10-27 10:01:30 +02:00
INSTALL
INSTALL.cmake docs: reduce/avoid English contractions 2021-11-07 23:16:27 +01:00
INSTALL.md docs/INSTALL: document how to use multiple TLS backends 2023-02-01 08:00:55 +01:00
INTERNALS.md INTERNALS: cleanup 2022-12-27 10:54:03 +01:00
KNOWN_BUGS cmake: set the soname on the shared library 2022-12-15 12:36:25 +01:00
MAIL-ETIQUETTE docs: remove him/her/he/she from documentation 2022-07-27 13:52:53 +02:00
Makefile.am copyright: update all copyright lines and remove year ranges 2023-01-03 09:19:21 +01:00
MANUAL.md MANUAL.md: add pipe to apt-key example 2022-12-28 09:19:02 +01:00
mk-ca-bundle.1 copyright: update all copyright lines and remove year ranges 2023-01-03 09:19:21 +01:00
MQTT.md docs: reduce/avoid English contractions 2021-11-07 23:16:27 +01:00
NEW-PROTOCOL.md docs: minor grammar fixes 2022-09-29 10:44:12 +02:00
options-in-versions src: add --http3-only 2023-01-12 16:18:05 +01:00
PARALLEL-TRANSFERS.md docs: spellfixes 2022-09-21 15:20:08 +02:00
README.md docs: reduce/avoid English contractions 2021-11-07 23:16:27 +01:00
RELEASE-PROCEDURE.md docs: spellfixes 2022-09-21 15:20:08 +02:00
ROADMAP.md spellcheck.words: remove 'github' as an accepted word 2022-10-27 15:53:11 +02:00
RUSTLS.md misc: typo and grammar fixes 2022-10-27 10:01:30 +02:00
SECURITY-PROCESS.md SECURITY-PROCESS.md: document severity levels 2022-12-21 16:26:35 +01:00
SSL-PROBLEMS.md misc: typo and grammar fixes 2022-10-27 10:01:30 +02:00
SSLCERTS.md docs: spellfixes 2022-09-21 15:20:08 +02:00
THANKS THANKS: 40 new contributors from 7.87.0 2022-12-21 08:00:59 +01:00
THANKS-filter copyright: update all copyright lines and remove year ranges 2023-01-03 09:19:21 +01:00
TheArtOfHttpScripting.md docs: spellfixes 2022-09-21 15:20:08 +02:00
TODO misc: Fix incorrect spelling 2022-12-06 23:18:23 +01:00
URL-SYNTAX.md test1275: verify upercase after period in markdown 2022-10-12 14:19:50 +02:00
VERSIONS.md docs: spellfixes 2022-09-21 15:20:08 +02:00
WEBSOCKET.md copyright: update all copyright lines and remove year ranges 2023-01-03 09:19:21 +01:00

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