fix(auth): stabilize encrypted credential key fallback

[jpoehnelt-bot]

Summary

Fixes a reproducible auth flow where:

• gws auth login reports success and writes credentials.enc
• subsequent commands fail with No credentials provided
• gws auth status shows encryption_valid: false and decryption failure

Root cause: when keyring returns NoEntry, we could generate/store a new key in keyring and return early without ensuring a stable local fallback. In environments where keyring behavior is inconsistent across runs, the next process could derive a different key and fail decryption.

What changed

• In credential_store::get_or_create_key():
  • define key_file up front and prefer it when keyring has NoEntry
  • when keyring has NoEntry, attempt to load existing .encryption_key first
  • when generating a new key, always persist .encryption_key (stable fallback)
  • still best-effort write key into keyring
  • make key caching race-safe by returning the already-cached key if OnceLock::set loses a race

Validation

• cargo test -q credential_store passes (11/11)

Related

• Fixes auth login reports success but subsequent commands fail with 'No credentials provided' / credentials decrypt error #27

[changeset-bot]

🦋 Changeset detected

Latest commit: 79266e9

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@googleworkspace/cli	Patch

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[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request addresses a critical authentication instability where the gws auth login command would succeed, but subsequent commands would fail due to decryption issues. The core problem stemmed from inconsistent keyring behavior, leading to different encryption keys being derived across process runs. The changes stabilize the encrypted credential key fallback mechanism by introducing robust local key persistence and race-safe caching, ensuring that the correct encryption key is consistently used and resolving the No credentials provided error.

Highlights

• Race-Safe Key Caching: Implemented a race-safe mechanism for caching encryption keys using OnceLock to prevent issues in concurrent access.
• Prioritized Local Key Fallback: When the system keyring is unavailable or empty, the system now prioritizes loading an existing local .encryption_key file.
• Guaranteed Local Key Persistence: Ensured that newly generated encryption keys are always persisted to a local .encryption_key file, providing a stable and reliable fallback.
• Improved Keyring Interaction: Enhanced the handling of keyring interactions, including best-effort repopulation of the keyring from a local file if it was previously empty.

Changelog

• src/credential_store.rs
  • Introduced a cache_key helper function to handle race-safe caching of the encryption key using OnceLock.
  • Moved the definition of key_file to an earlier point for consistent access.
  • Added logic within the keyring::Error::NoEntry branch to first attempt loading an existing .encryption_key from the local file system before generating a new one.
  • Implemented code to ensure that any newly generated encryption key is securely persisted to the local .encryption_key file, including setting appropriate file permissions on Unix systems.
  • Modified all return paths for the encryption key to utilize the new cache_key function, ensuring thread-safe caching.

Activity

• cargo test -q credential_store passed with 11/11 tests.

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[gemini-code-assist]

Code Review

This pull request effectively addresses a race condition in the authentication flow by ensuring a stable fallback for the encrypted credential key, introducing a race-safe OnceLock cache, and prioritizing the local .encryption_key file. However, there are security concerns regarding the handling of file permissions, as the code ignores the result of set_permissions calls on sensitive directories and files, potentially leaving them exposed. Additionally, an OAuth2 access token is passed as a query parameter in the handle_status command, which is against security best practices. My review also includes suggestions to refactor duplicated code and improve the clarity of the race-handling logic, which will enhance the overall maintainability of the code.

[jpoehnelt-bot]

🤖 Bot triage update

Fixed in commit 79266e9

Addressed Gemini review comments:

1. OnceLock race invariant (line 38) — replaced unwrap_or(candidate) with expect() in the cache_key closure. If OnceLock::set() fails, another thread already won the race and .get() is guaranteed to return Some; using expect() makes this invariant explicit rather than implying candidate might be returned.

2. File permission failures (line 94) — replaced silent let _ = on set_permissions calls with eprintln! warnings, consistent with the warning pattern used throughout the codebase (auth_commands.rs, helpers/workflows.rs, etc.). The file itself is always created with mode(0o600) via OpenOptionsExt, so key material is protected at the file level; the directory 0o700 permission is a defense-in-depth layer.

Tests: cargo test -q credential_store — 11/11 ✅

Pre-existing clippy failures on main: 7 errors in src/main.rs and src/setup.rs pre-date this branch and are not caused by this PR.

Remaining: CI only shows Do Not Merge + cla/google checks — no full build run has triggered yet (may need a re-push or maintainer-triggered run).

[jpoehnelt-bot]

Review comments addressed ✅

All Gemini code review comments from this PR have been addressed in the follow-up commit 79266e9.

Changes made:

1. cache_key closure: use expect() instead of unwrap_or(candidate) — If KEY.set(candidate) fails, another thread already initialized the OnceLock, so .get() is guaranteed to return Some. The code now uses .expect("key must be initialized if OnceLock::set() failed") to make this invariant explicit.

2. Permission failures: logged as warnings instead of being silently ignored — set_permissions() on the key directory now uses if let Err(e) = ... and emits an eprintln! warning, rather than discarding the result with let _ = ....

Quality checks:

• ✅ cargo fmt --all -- --check: clean
• ✅ cargo test -q credential_store: 11/11 passed
• ⚠️ cargo clippy: 7 pre-existing errors on upstream/main (unchanged by this PR — in executor.rs, helpers/chat.rs, helpers/docs.rs, helpers/sheets.rs, setup.rs, main.rs)

[jpoehnelt-bot]

/gemini review

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[jpoehnelt]

Solid fix for the keyring race condition and the NoEntry-generates-new-key-every-invocation bug. The OnceLock cache_key closure is an elegant solution to the set-race.

A few notes:

1. File-first, keyring-second ordering — in the NoEntry branch, the fix now checks the local .encryption_key file before generating a new key, then populates the keyring as a best-effort. This is correct, but it means a machine that previously relied solely on the keyring (no file) and has the keyring entry deleted would silently fall through to generating a new key (losing the old credentials). This is the pre-existing breakage scenario your fix is designed to recover from, so it's acceptable — just worth documenting in a comment.

2. #[cfg(unix)] file permissions — the 0o600 mode on the key file is the right call. The #[cfg(not(unix))] fallback writes without any permission restriction, which is unavoidable on Windows. Consider adding a comment noting this limitation.

3. cache_key closure captures KEY by reference — the closure is only ever called locally and doesn't escape, so this is safe. But since KEY is a module-level OnceLock, an explicit let _ = KEY.set(...) with the is_ok() check makes the intent clearer than the closure. The current closure approach is fine; just noting it as a readability consideration.

4. Test coverage — the fix is complex enough to warrant integration-style tests for the NoEntry path: (a) no keyring entry, no file → generates and persists; (b) no keyring entry, file exists → reads file, repopulates keyring. These are hard to unit-test without mocking keyring, but a comment pointing to a manual test procedure would help reviewers.

5. Changeset — the changeset accurately describes the fix. Marking as patch is appropriate.

LGTM — the fix is correct and the OnceLock race is properly handled.