5 Commits

Author	SHA1	Message	Date
dillard	f18b4f0862	Phase 2: disaster recovery (occ backup:restore:full) ... New commands, per PLAN.md 3.7: - occ backup:key:import: adopt the master key from a recovery kit on a fresh installation (instead of occ backup:key:init generating a new one), so occ backup:target:add opens the existing repository on the location rather than creating an empty one. - occ backup:restore:full: replace the database (consistent, one transaction), restore the data directory in place, and merge config.php -- refuses up front and lists what's missing when the Nextcloud major version or any app enabled at backup time doesn't match here (their tables must exist before the database restore can use them), rather than guessing or partially applying. Repository::restore() gained an optional $stripPrefix (write "data/<uid>/..." straight into the real data directory, not a "data/" subdirectory of it) -- restoring "data/" and "config/" this way needs no temporary copy of what can be the largest part of an instance. occ backup:target:add now backfills the local snapshot cache (ngb_snapshots, what occ backup:list actually reads) when it adopts an existing repository: without this, a freshly connected location showed no restore points at all, even though the repository itself had them. One unreadable snapshot is skipped rather than aborting the backfill or the target add itself. Three self-referential problems found and fixed by testing this against two real, separate Nextcloud instances sharing only the backup location (tests/integration/full-restore-roundtrip.sh covers this; the per-process nature of these bugs meant they were invisible from inside a single occ invocation, including the one used to write the fixes, which is exactly why a second, fresh process re-running occ backup:status etc. was necessary to catch them): - The full database dump includes ng_backup's own tables and appconfig rows; restoring them verbatim would overwrite the key/target that is actively performing the restore, on THIS installation, with the backed-up instance's. Both are now preserved: ng_backup's own tables (and, on PostgreSQL, their sequences -- excluding a table does not exclude its sequence) are excluded from what gets restored, and its appconfig rows are captured before the database restore and written back after, in their own transaction. - config.php's 'secret' is merged in from the backup (needed so already-encrypted content in the restored database, e.g. share tokens, stays decryptable), but Target::options, the master key, the wrapped key and the recovery kit code are all encrypted with that same instance secret (OCP's ICrypto, or Nextcloud AppConfig's own "sensitive" flag underneath), not with ng_backup's own key. Changing it without re-encrypting them first left all four permanently undecryptable the moment any later occ command ran. Fixed with two helpers (TargetService::reencryptOptionsAround(), KeyService::reencryptForSecretRotation()) that decrypt before and re-encrypt after whatever callback actually changes the secret; config.php is applied dead last in restoreFull(), after every other repository access. Not crash-safe (a process kill mid-rotation would leave a key missing, not just stale) -- disaster recovery is run once by hand, right after occ maintenance:install, a window too narrow yet to justify a two-phase write. - A subtler variant of the same bug: Nextcloud's own AppConfig additionally encrypts a "sensitive" value itself, tied to the same secret, underneath our own encryption. Overwriting an existing sensitive key makes it read the old value first to compare, which then also fails against the new secret. Deleting the key before setting the new value avoids that read entirely. Roadmap (PLAN.md 9): phase 3 (in-place full restore, user self-service) moved out to v1.3.0; phase 2 continues toward v1.2.0 with FTP/SMB, a verification/checksum-audit command, user-export retention, and deciding whether per-user export joins the automatic schedule.	2026-10-05 23:31:08 +02:00
dillard	e7229626f8	Prepare the 0.1.0-alpha.1 release ... info.xml's version field is restricted by Nextcloud's own info.xsd to plain numeric SemVer, no pre-release suffix, so the alpha/beta/rc stage from PLAN.md's release table lives in the git tag and CHANGELOG instead; noted that in PLAN.md so it isn't rediscovered later. Bumped the version, wrote an honest description for an alpha (feature-complete for phase 1, not for production), and added CHANGELOG.md. README: new "Storage backend experiences" section, seeded with the Hetzner Storage Box sub-account root-path quirk found while testing a real SFTP target (root must be "home", not "/"), open for others to extend via PR.	2026-10-05 11:45:48 +02:00
dillard	066873a818	Plan: release stages and version numbers	2026-10-02 13:16:54 +02:00
dillard	06e55b08ea	Plan: decisions after phase 0 (files_external state, per-user restore, versions)	2026-10-01 18:50:57 +02:00
dillard	07e3d263b4	Phase 0: skeleton, streaming encryption (spike A) ... Repository skeleton (app id ng_backup, AGPL-3.0-or-later), KeyRing with KDF subkeys, keyed blob ids and Argon2id key wrapping, and StreamCipher (secretstream XChaCha20-Poly1305, framed, bounded memory). Spike A: 1 GiB round trip with memory_limit=64M, peak < 2 MiB, ~160/122 MiB/s; tampering, truncation, wrong key/passphrase are rejected.	2026-10-01 18:15:24 +02:00