Bug 267868 – Check curl version for HTTP/3 support

• Status: REOPENED
• Component: CMake

[Don Olmstead]

Not experimental since 8.5.0

[Don Olmstead]

Pull request: https://github.com/WebKit/WebKit/pull/23056

[EWS]

Committed 273520@main (561efe11068f): <https://commits.webkit.org/273520@main>

Reviewed commits have been landed. Closing PR #23056 and removing active labels.

[WebKit Commit Bot]

Re-opened since this is blocked by bug 268138

[Radar WebKit Bug Importer]

<rdar://problem/121868520>

[Kenji Shukuwa]

The reason why LayoutTests failed, as reported in bug 268138, was because the CURLE_RECV_ERROR(56) error was returned
when there was a certificate error . Before this patch , the CURLE_PEER_FAILED_VERIFICATION(60) error was returned
when there was a certificate error, and resources could be obtained after the server trust evaluation process. However,
because the CURLE_RECV_ERROR error was returned, this process was not performed, and resources could not be obtained.

The reason why CURLE_PEER_FAILED_VERIFICATION was returned was because CURLOPT_HTTP_VERSION was set to
CURL_HTTP_VERSION_3. Normally, the decision on whether to use HTTP/3 communication should be based on the alt-svc
settings, but when CURL_HTTP_VERSION_3 is set, the initial communication will be performed in HTTP/3 regardless of the
alt-svc settings. The curl uses ngtcp2 internally when performing HTTP/3 communication, but ngtcp2 functions continue
to be used even after falling down to HTTP/2 communication. In this case, an error occurs in the ngtcp2 function during
processing after detecting a certificate error, which causes the CURLE_RECV_ERROR error to be returned.

To follow the Alt-Svc settings, set CURLOPT_HTTP_VERSION to CURL_HTTP_VERSION_NONE. This will allow curl to
communicate with the appropriate HTTP version based on information from ALPN, alt-svc, etc.

[Kenji Shukuwa]

Pull request: https://github.com/WebKit/WebKit/pull/45817

[Kenji Shukuwa]

Don, could you please assign a reviewer?