`sshd -t` folds two questions into one exit code — is the merged config
parseable, and is the privilege-separation directory there. Both call
sites ran it as `sshd -t 2>/dev/null` and read any non-zero exit as the
first question's answer, discarding the line that named the second.
Bootstrap aborted with "sshd rejects the merged config", a verdict sshd
never reached, and sent the operator to audit /etc/ssh files that were
never broken. /run is a tmpfs and /run/sshd is ssh.service's
RuntimeDirectory, so it is legitimately absent under socket activation
on a box whose SSH door is serving connections normally.
Classification is now a pure, sourceable sshd_privsep_gap: the status is
the verdict, the text only classifies a failure, so a passing sshd -t is
never diverted. sshd_config_ok repairs the gap with an idempotent
install -d and retests once. A genuine parse refusal still refuses and
the rollback is untouched.
Refusals now carry sshd's own stderr. users-close-root had the identical
three lines and now reaches the shared judgement through lib/sshd.sh
instead of keeping a second copy of it.
Fixes#92
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>