Bug 311725 – CredentialsContainer::get(): credential type combination check is incomplete — only validates publicKey and digital

• Component: WebCore Misc.
• Status: NEW

[Marcos Caceres]

The combination check added in bug 310788 (PR #62231) only validates publicKey/digital combinations. It does not correctly handle combinations involving password, federated, identity, or otp.

Per https://github.com/w3c/webappsec-credential-management/pull/261, the registry defines "Types allowed in the same get() request":

  digital    → empty (cannot mix with any other type)
  federated  → password only
  identity   → empty
  otp        → empty
  password   → federated only
  publicKey  → empty

The spec algorithm says (verbatim):
"If |type1|'s types allowed in the same get() request doesn't contain |type2|, then return a promise rejected with a NotSupportedError DOMException."

Current bugs:

1. { publicKey: {...}, password: true } — should NotSupportedError, but currently passes and silently ignores password.
2. { digital: {...}, password: true } — same problem.
3. { password: true, federated: {...} } — valid combo per spec, but we reject with "Missing request type" since we only look for publicKey/digital.
4. { password: true } alone — valid (if unimplemented) type, but we reject with "Missing request type".

Fix: validate all combinations against the registry table. For unimplemented types (password, federated, identity, otp), return null rather than "Missing request type".

[Radar WebKit Bug Importer]

<rdar://problem/174313024>