fix(connection): judge an entry's explicit port from the parsed URL, not the raw string

WHATWG trimming strips stray whitespace before parsing, so 'host:port ' passed
the load assert while the raw-string port regex read it as port-less —
broadening an exact-port grant to every port on that hostname. The explicit-
port judgment now reads URL parses under both special schemes (:80/:443 stay
explicit), and the load assert refuses whitespace outright.

packages/client/connection/src/api-request-trust.ts

@@ -45,16 +45,29 @@ function parseAuthority(authority: string): URL | undefined {
  * `host:port`) and nothing else. WHATWG parsing would quietly read a hostname
  * out of `harness.internal/path` or `user@harness.internal` — a typo must fail
  * the load loudly instead of authorizing its hostname or being ignored until
- * requests 403. The delimiter test refuses every URL part beyond the authority
- * (path, backslash path, query, fragment, userinfo); IPv6 brackets use none of
+ * requests 403. The character test refuses every URL part beyond the authority
+ * (path, backslash path, query, fragment, userinfo) and all whitespace, which
+ * WHATWG trimming would otherwise strip silently; IPv6 brackets use none of
  * them.
  * @param entry - the configured value, verbatim.
  */
 export function assertTrustedAuthority(entry: string): void {
-  if (parseAuthority(entry) !== undefined && !/[/\\?#@]/.test(entry)) return
+  if (parseAuthority(entry) !== undefined && !/[/\\?#@\s]/.test(entry)) return
   throw new Error(`client-connection: trustedHosts entry ${JSON.stringify(entry)} is not a bare host[:port] authority`)
 }
 
+/**
+ * Whether the parsed authority carries an explicit port: judged from URL
+ * parses under both special schemes (their default ports differ, so `:80` and
+ * `:443` still count as explicit), never from the raw string, where WHATWG
+ * trimming of stray whitespace would misread `host:port ` as port-less and
+ * broaden an exact-port grant to every port.
+ */
+function hasExplicitPort(entry: string, entryUrl: URL): boolean {
+  // An authority that parsed under http cannot fail under https.
+  return entryUrl.port !== '' || new URL(`https://${entry}`).port !== ''
+}
+
 /**
  * Whether the request authority matches a `trustedHosts` entry. An entry with
  * an explicit port matches that exact authority; a port-less entry matches the
@@ -66,7 +79,7 @@ function isTrustedAuthority(hostUrl: URL, trustedHosts: readonly string[]): bool
   return trustedHosts.some((entry) => {
     const entryUrl = parseAuthority(entry)
     if (entryUrl === undefined) return false
-    return /:\d+$/.test(entry)
+    return hasExplicitPort(entry, entryUrl)
       ? entryUrl.host === hostUrl.host
       : entryUrl.hostname === hostUrl.hostname
   })

packages/client/connection/tests/api-request-trust.spec.ts

@@ -75,6 +75,18 @@ describe('isTrustedApiRequest', () => {
     for (const entry of ['harness.internal/path', 'harness.internal/', 'user@harness.internal', 'harness.internal?x', 'harness.internal#f', 'harness.internal\\path', 'bad entry', '']) {
       expect(() => { assertTrustedAuthority(entry) }).toThrow(/not a bare host\[:port\] authority/)
     }
+    // WHATWG trimming would silently strip these; the entry must fail instead.
+    for (const entry of ['harness.internal:3080 ', ' harness.internal', 'harness.internal:30\t80']) {
+      expect(() => { assertTrustedAuthority(entry) }).toThrow(/not a bare host\[:port\] authority/)
+    }
+  })
+
+  it('never lets stray whitespace broaden an exact-port entry to every port', () => {
+    // Defense in depth below the load-time assert: the explicit-port judgment
+    // reads the parsed URL, so a trimmed `host:port ` entry stays exact.
+    const trusted = ['harness.internal:3080 ']
+    expect(isTrustedApiRequest(request({ host: 'harness.internal:9999', origin: 'http://harness.internal:9999' }), trusted)).toBe(false)
+    expect(isTrustedApiRequest(request({ host: 'harness.internal:3080', origin: 'http://harness.internal:3080' }), trusted)).toBe(true)
   })
 
   it('refuses malformed or untrusted authorities on browser requests', () => {