Allow additive csp configuration (#102059) (#103405)

* add additive csp configuration

* add unit tests for new class

* fix types

* adapt test utils

* fix tests

* more unit tests on config

* generated doc

* review comments

* update ascii doc

* update ascii doc links

* automatically add single quotes for keywords

* add missing csp directives

* add more tests

* add additional settings to asciidoc

* add null-check

* revert test config props

* fix usage collection usage

* some review comments

* last review comments

* add kibana-docker variables

* try to fix doc reference

* try to fix doc reference again

* fix tests
# Conflicts:
#	src/core/server/csp/config.ts
#	src/core/server/csp/csp_config.test.ts

docs/development/core/server/kibana-plugin-core-server.cspconfig.__private_.md

@@ -0,0 +1,11 @@
+<!-- Do not edit this file. It is automatically generated by API Documenter. -->
+
+[Home](./index.md) &gt; [kibana-plugin-core-server](./kibana-plugin-core-server.md) &gt; [CspConfig](./kibana-plugin-core-server.cspconfig.md) &gt; ["\#private"](./kibana-plugin-core-server.cspconfig.__private_.md)
+
+## CspConfig."\#private" property
+
+<b>Signature:</b>
+
+```typescript
+#private;
+```

docs/development/core/server/kibana-plugin-core-server.cspconfig.md

@@ -20,6 +20,7 @@ The constructor for this class is marked as internal. Third-party code should no
 
 |  Property | Modifiers | Type | Description |
 |  --- | --- | --- | --- |
+|  ["\#private"](./kibana-plugin-core-server.cspconfig.__private_.md) |  | <code></code> |  |
 |  [DEFAULT](./kibana-plugin-core-server.cspconfig.default.md) | <code>static</code> | <code>CspConfig</code> |  |
 |  [disableEmbedding](./kibana-plugin-core-server.cspconfig.disableembedding.md) |  | <code>boolean</code> |  |
 |  [header](./kibana-plugin-core-server.cspconfig.header.md) |  | <code>string</code> |  |

docs/setup/settings.asciidoc

@@ -36,11 +36,57 @@ Set to `false` to disable Console. *Default: `true`*
  <<ops-cGroupOverrides-cpuAcctPath, `ops.cGroupOverrides.cpuAcctPath`>>.
 
 | `csp.rules:`
- | A https://w3c.github.io/webappsec-csp/[content-security-policy] template
+ | deprecated:[7.14.0,"In 8.0 and later, this setting will no longer be supported."] 
+A https://w3c.github.io/webappsec-csp/[Content Security Policy] template
 that disables certain unnecessary and potentially insecure capabilities in
 the browser. It is strongly recommended that you keep the default CSP rules
 that ship with {kib}.
 
+| `csp.script_src:`
+| Add sources for the https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/script-src[Content Security Policy `script-src` directive].
+
+| `csp.worker_src:`
+| Add sources for the https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/worker-src[Content Security Policy `worker-src` directive].
+
+| `csp.style_src:`
+| Add sources for the https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/style-src[Content Security Policy `style-src` directive].
+
+| `csp.connect_src:`
+| Add sources for the https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/connect-src[Content Security Policy `connect-src` directive].
+
+| `csp.default_src:`
+| Add sources for the https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/default-src[Content Security Policy `default-src` directive].
+
+| `csp.font_src:`
+| Add sources for the https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/font-src[Content Security Policy `font-src` directive].
+
+| `csp.frame_src:`
+| Add sources for the https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/frame-src[Content Security Policy `frame-src` directive].
+
+| `csp.img_src:`
+| Add sources for the https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/img-src[Content Security Policy `img-src` directive].
+
+| `csp.frame_ancestors:`
+| Add sources for the https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/frame-ancestors[Content Security Policy `frame-ancestors` directive].
+
+|===
+
+[NOTE]
+============
+The `frame-ancestors` directive can also be configured by using 
+<<server-securityResponseHeaders-disableEmbedding, `server.securityResponseHeaders.disableEmbedding`>>. In that case, that takes precedence and any values in `csp.frame_ancestors` 
+are ignored.
+============
+
+[cols="2*<"]
+|===
+
+| `csp.report_uri:`
+| Add sources for the https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/report-uri[Content Security Policy `report-uri` directive].
+
+| `csp.report_to:`
+| Add sources for the https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/report-to[Content Security Policy `report-to` directive].
+
 |[[csp-strict]] `csp.strict:`
  | Blocks {kib} access to any browser that
 does not enforce even rudimentary CSP rules. In practice, this disables
@@ -538,8 +584,7 @@ a|`server.securityResponseHeaders:`
 is used in all responses to the client from the {kib} server, and specifies what value is used. Allowed values are any text value or `null`.
 To disable, set to `null`. *Default:* `null`
 
-[[server-securityResponseHeaders-disableEmbedding]]
-a|`server.securityResponseHeaders:`
+|[[server-securityResponseHeaders-disableEmbedding]]`server.securityResponseHeaders:`
 `disableEmbedding:`
 | Controls whether the https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy[`Content-Security-Policy`] and
 https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Frame-Options[`X-Frame-Options`] headers are configured to disable embedding