Steps 3-6 of stage 3 and what the two reviews found in steps 1-6, in one
commit: the review fixes sit in the same hunks.
Step 3, CLI backup (M3, M5, L1, L2; L4 of the stage's list):
- backup.snapshotDB refuses a database that is not there and opens the
source mode=ro (measured: mode=ro creates no file).
- selfpost-backup holds an encrypting password to
validate.MinSecretFilePasswordLen; -o of both directions writes a
temporary file beside the name and renames it whole; -decrypt peeks the
first chunk (password and type authenticated) before the output exists.
- what a backup leaves out (a link under data/, a link under certs/ to a
directory, a socket...) is told to OnWarn; certs/ with no file is
backup.ErrNoCerts, refused by Check and Create, named by the panel.
- parseTrustedProxies: a bare address takes /128 when written with a
colon (::ffff:10.0.0.1/32 was ::/32).
Step 4, secretfile (M4, L3): scrypt's V at most 128 MiB, r <= 64, p <= 2;
bytes after the last chunk are ErrCorrupt.
Step 5 (L7): atomicfile.SyncDir after the rename, used by Write,
replaceSASLDB and the CLI; atomicfile_test.go.
Step 6: security.md and guide on backup and restore.
Reviews (technical, security):
- H1: a restore of a server with DMARC on was refused on every start - the
archive records no owner, tar as root left the DMARC maps root's, and the
entrypoint only chowned the maps it named. It now hands every file beside
queue/ in /data/postfix to panel:selfpost 0640; e2e writes an extra map
before the backup and finds it panel:selfpost 640 after a root unpack.
- the comparison reads regular files only (Lstat, size, LimitReader); a
record unpacked again wins over the earlier check's mark; ConsumeRestore
removes both; the mark is synced; a journal file beside a freshly unpacked
database is refused.
- AttachRefusalLine refuses an empty line as the old statement did; skipped
entries named in words; -decrypt of an empty payload is no failure; guide
wording on the shell's '>' and a killed CLI; the in-place restore's
'mv .' (older than this stage) fixed.
Tested on the test server: go vet + go test of 25 packages, make e2e (all
pass, 643 s) on this tree.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>