`connection.json` under the desktop app's Electron `userData` was written with no
file mode, so it landed at the `0644` umask default — while its two
credential-bearing neighbours in the same directory, `desktop-installation.json`
and `native-oauth-tokens.json`, were already `0600`. That file holds the
safeStorage-encrypted gateway token plus the fields that are NOT encrypted: the
gateway URL and the SSH host, user, and key path.
- Route the single write choke point through a helper that creates the file
owner-only and atomically.
- Tighten an already-existing `0644` file once per launch on the read path, so
installs that already have one do not stay world-readable until the next save.
- Refuse to act on a path that is a symlink or not owned by the current user,
matching the guards `desktop-installation.ts` already applies to its sibling.
The symlink guard alone turned out to be insufficient, and that is worth
recording: `writeSecretFileAtomic` tightens its *temp* path, so a symlink planted
at `connection.json.tmp` meant `writeFileSync` followed it, the guard correctly
bailed, and `renameSync` then moved the link onto `connection.json` permanently.
Measured, guard-only vs. as-landed:
guards only token leaked: true config is a symlink: true 755
guards + temp unlink token leaked: false config is a symlink: false 600
So the temp path is unlinked before the write.
Issue #77486's headline claim — that a dashboard session token is persisted in
plaintext — does not hold against main. The token has been safeStorage-encrypted
since the desktop app reached mainline in 51c68d4ab, and `encryptDesktopSecret`
aborts with an actionable message rather than degrading to plaintext when
safeStorage is unavailable. The `{ encoding: 'plain', value }` literal does exist
at main.ts:7084, but only on the `persistToken: false` branch, whose sole caller
is the connection-test handler, which never writes. So no mainline path *writes*
a plaintext token. The commits that did contain a plaintext-writing fallback
(d3d177283, d208f2c2c) are not ancestors of main — they live only on
upstream/bb/gui-* and the desktop-pr20059-installers pre-release tag.
At-rest migration of legacy non-safeStorage payloads is deliberately NOT included.
An earlier revision of this branch implemented it and it was removed after review
reproduced two token-loss paths: it force-converts the opt-in plaintext choice
PR #62319 adds (silently reverting the user's decision, then destroying the token
on the next launch without the `--password-store=basic` flag), and it converts a
portable credential into a keychain-bound one with no consent — destroying the
only recoverable copy while not remediating the real exposure, since every
existing backup still holds the plaintext and the true remedy is rotation. It also
persisted raw `parsed`, bypassing `sanitizeConnectionProfiles`. A comment at the
read path records the three preconditions any future attempt needs.
`decryptDesktopSecret`'s non-safeStorage read fallback is untouched — it is what
lets a pre-release or hand-edited config work at all.
Windows still inherits the userData directory ACL rather than an explicit
owner-only one; mode bits are advisory there, so that half is deferred to
PR #77527 rather than growing a second ACL implementation here.
e2e: `at-rest-connection-token.spec.ts` asserts the at-rest contract
implementation-independently — the token's plaintext value (and its base64 form)
must not appear in a raw-bytes scan of any file under userData or HERMES_HOME,
AND the app must still put the exact original token on the wire after a restart,
so a fix that simply drops the token cannot pass. Proven non-vacuous by mutation:
writing `{ encoding: 'plain', value }` still fails the scan while the
file-exists and gateway-URL guards pass. The migration case is a documented
`test.fixme` naming its three blockers.
Electron project 928 -> 924 tests (-9 migration, +5 new guard and
mechanism-isolation). Two of those five exist because reverting either owner-only
mechanism alone initially scored zero failures — they were masking each other, so
either could have been deleted green.
(cherry picked from commit 6e01add6578f08f015a567d3a7a7378f2ec3e768)
张豪杰
7e151bd9d3