fix(cua-driver): report inaccessible Windows daemon pipes - #3318
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fix(cua-driver): report inaccessible Windows daemon pipes#3318injaneity wants to merge 2 commits into
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Verified at 57bd56f9e9b7215537800e47d61eb043d2810ace after integrating current main without rewriting the contributor commit. Formatting and the focused driver binary check pass, the prior two-SID Windows OpenSSH replay covers the intended inaccessible-pipe diagnostic, and all current checks are green: 38 successful with one intentional release-metadata skip.
This does not provide the unavailable private Fleet Server 2025 replay, but the final two-file diff is unchanged in behavior from the previously replayed Windows candidate and the exact-head Windows compile/unit lane passes.
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summary
cua-driver statusreports that the daemon is runningsessionfield from the documentedstatusoutputcloses #2771
root cause
The Windows daemon pipe is intentionally private to the SID that owns the interactive daemon.
WaitNamedPipeW, which backed the firststatuscheck, proves that the pipe name exists without proving that the caller may open it. A different SSH account therefore saw “daemon is running” fromstatus, then received Windows error 5 when MCP attempted the real connection.Session 0 is not the blocker. A same-SID Session 0 client can connect to the interactive Session 1 daemon.
validation
Exact head:
57bd56f9e9b7(currentmainintegrated; contributor commitbbebabcd5preserved)Live Windows OpenSSH replay against an elevated interactive Cua daemon:
-1000-1001statusdetected the pipemcp --socket \.\pipe\cua-driverfailed withAccess is denied. (os error 5)-1000initializeand returned the Cua server responseThe temporary SSH key, test binary, account allowance, and ACL changes were removed after the replay; the original OpenSSH configuration was restored.
Also checked:
git diff --checkstatusperformssend_requestbefore printing “daemon is running”Current-main integration validation:
cargo fmt --check --all,cargo check -p cua-driver --bin cua-driver, andgit diff --check origin/main...HEADpass locally. Fresh exact-head pull request CI, including the hosted Windows compile lane, is running. The earlier live two-SID OpenSSH replay remains behavior evidence because the integration merge did not change this two-file patch.