Add origin checks to web sockets (#6048)

* Move splitOnFirstEquals to util

I will be making use of this to parse the forwarded header.

* Type splitOnFirstEquals with two items

Also add some test cases.

* Check origin header on web sockets

* Update changelog with origin check

* Fix web sockets not closing with error code

src/node/cli.ts

@@ -3,7 +3,15 @@ import { promises as fs } from "fs"
 import { load } from "js-yaml"
 import * as os from "os"
 import * as path from "path"
-import { canConnect, generateCertificate, generatePassword, humanPath, paths, isNodeJSErrnoException } from "./util"
+import {
+  canConnect,
+  generateCertificate,
+  generatePassword,
+  humanPath,
+  paths,
+  isNodeJSErrnoException,
+  splitOnFirstEquals,
+} from "./util"
 
 const DEFAULT_SOCKET_PATH = path.join(os.tmpdir(), "vscode-ipc")
 
@@ -292,19 +300,6 @@ export const optionDescriptions = (opts: Partial<Options<Required<UserProvidedAr
   })
 }
 
-export function splitOnFirstEquals(str: string): string[] {
-  // we use regex instead of "=" to ensure we split at the first
-  // "=" and return the following substring with it
-  // important for the hashed-password which looks like this
-  // $argon2i$v=19$m=4096,t=3,p=1$0qR/o+0t00hsbJFQCKSfdQ$oFcM4rL6o+B7oxpuA4qlXubypbBPsf+8L531U7P9HYY
-  // 2 means return two items
-  // Source: https://stackoverflow.com/a/4607799/3015595
-  // We use the ? to say the the substr after the = is optional
-  const split = str.split(/=(.+)?/, 2)
-
-  return split
-}
-
 /**
  * Parse arguments into UserProvidedArgs.  This should not go beyond checking
  * that arguments are valid types and have values when required.