This commit adds an OpenID Connect authentication realm to
elasticsearch. Elasticsearch (with the assistance of kibana or
another web component) acts as an OpenID Connect Relying
Party and supports the Authorization Code Grant and Implicit
flows as described in http://ela.st/oidc-spec. It adds support
for consuming and verifying signed ID Tokens, both RP
initiated and 3rd party initiated Single Sign on and RP
initiated signle logout.
It also adds an OpenID Connect Provider in the idp-fixture to
be used for the associated integration tests.
This is a backport of #40674
This change updates our version of httpclient to version 4.5.8, which
contains the fix for HTTPCLIENT-1968, which is a bug where the client
started re-writing paths that contained encoded reserved characters
with their unreserved form.
The apache commons http client implementations recently released
versions that solve TLS compatibility issues with the new TLS engine
that supports TLSv1.3 with JDK 11. This change updates our code to
use these versions since JDK 11 is a supported JDK and we should
allow the use of TLSv1.3.
Ioannis Kakavas
Jay Modi
Armin Braun
Ryan Ernst