The app now writes a diagnostic log to nexus.log in the data directory
(0600, rotated at 5 MiB): connection attempts and results, remote
closes, reconnect scheduling, host-key/certificate checks with the
policy applied, and credentials that couldn't be stored (kind only).
Credentials and terminal data are never logged. RUST_LOG sets the level
and also mirrors the log to stderr. The remaining eprintln! diagnostics
in storage and URL handling go through it too.
Session-only credentials (kept for a whole session so reconnects don't
re-prompt), credentials pending until a connection succeeds, and the
credential prompt's text buffer are now Zeroizing and wiped when
dropped, including when a prompt is cancelled or abandoned
(SEC-20261012-007, partial).
Still open: the values handed to the protocol clients are plain Strings
for the duration of authentication, egui keeps its own copies of typed
text, and no mlock/PR_SET_DUMPABLE is applied.
Every shared lock was std::sync::Mutex with lock().unwrap() (~150 sites),
so a panic in any session's reader or callback poisoned the lock and the
next UI frame panicked too, dropping every open session. Locks are now
parking_lot::Mutex (no poisoning; already in the dependency tree), and a
panic hook reports worker panics as an error toast instead of the session
silently stopping (F3, F4).
Andy Dixon