Add DNSSEC signing, key backups and Porkbun support

Zones get a DNSSEC setting: named signs them with BIND's default (or a
custom) dnssec-policy and inline signing, with keys in a per-view key
directory. Jarl shows the keys, the DS record and when it is safe to
publish it, checks the parent's DS records (check-ds, which also tells
named), and refuses steps that would break a signed domain: switching
straight to unsigned, finishing a turn-off too early, deleting or moving
a signed zone, TTLs above max-zone-ttl. Turning off goes through the
insecure policy; wipe starts over once the parent has no DS.

Backups store the DNSSEC keys and restore puts them back for named; the
backup unit gets CAP_DAC_READ_SEARCH to read them. Jarl raises a zone's
serial above named's whenever it writes an older one (after a restore).
The serials check compares the signed serial.

With a Porkbun API key in jarl.yaml, the registrar's name servers, glue
records and DS records can be shown and changed, each change checked
first (dry run, force to override).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/engine/engine.go

@@ -122,6 +122,8 @@ type ApplyOptions struct {
 	Force bool
 	// NoReload writes the files without reloading named.
 	NoReload bool
+	// wipeZone lets WipeDNSSEC switch signing off for this zone at once.
+	wipeZone int64
 }
 
 func (e *Engine) replay(base *model.State, ops []model.Op, p *auth.Principal) (*model.State, []string, error) {
@@ -397,11 +399,11 @@ func (pl *plan) files() []string {
 	return out
 }
 
-func (e *Engine) makePlan(ctx context.Context, base, work *model.State, user string) (*plan, error) {
+func (e *Engine) makePlan(ctx context.Context, base, work *model.State, user string, opts ApplyOptions) (*plan, error) {
 	pl := &plan{base: base, work: work, verify: map[int64]uint32{}}
 	before := e.validate(base)
 	after := e.validate(work)
-	pl.introduced = validate.Introduced(before, after)
+	pl.introduced = append(validate.Introduced(before, after), e.dnssecChanges(base, work, opts)...)
 	introducedKeys := map[string]bool{}
 	for _, p := range pl.introduced {
 		introducedKeys[p.Key()] = true
@@ -415,6 +417,12 @@ func (e *Engine) makePlan(ctx context.Context, base, work *model.State, user str
 		return pl, nil
 	}
 	pl.serials = bumpSerials(base, work, e.Now(), user)
+	guarded, problems := e.guardSerials(ctx, base, work, pl.serials, user)
+	pl.serials = append(pl.serials, guarded...)
+	if validate.HasErrors(problems) {
+		pl.introduced = append(pl.introduced, problems...)
+		return pl, nil
+	}
 	pl.out = render.Render(work, e.cfg.Paths, e.cfg.Extras)
 	deployed, err := e.store.DeployedFiles(ctx)
 	if err != nil {
@@ -498,6 +506,11 @@ func (e *Engine) stagingCheck(ctx context.Context, pl *plan) error {
 	defer os.RemoveAll(dir)
 	sp := render.Paths{ConfigDir: filepath.Join(dir, "config"), ZoneDir: filepath.Join(dir, "zones"), CacheDir: filepath.Join(dir, "cache")}
 	sout := render.Render(pl.work, sp, e.cfg.Extras)
+	for _, d := range sout.Dirs {
+		if err := os.MkdirAll(d, 0o750); err != nil {
+			return err
+		}
+	}
 	for _, f := range sout.Files {
 		if err := os.MkdirAll(filepath.Dir(f.Path), 0o750); err != nil {
 			return err
@@ -635,7 +648,7 @@ func (e *Engine) Preview(ctx context.Context, csID int64, p *auth.Principal) (*R
 		res.Error = ee
 		return res, nil
 	}
-	pl, err := e.makePlan(ctx, base, work, p.Name())
+	pl, err := e.makePlan(ctx, base, work, p.Name(), ApplyOptions{})
 	if err != nil {
 		return nil, err
 	}
@@ -714,7 +727,7 @@ func (e *Engine) applyOps(ctx context.Context, cs *model.Changeset, reqs []Reque
 			cs.Description += fmt.Sprintf(" (+%d more)", len(cs.Ops)-1)
 		}
 	}
-	pl, err := e.makePlan(ctx, base, work, p.Name())
+	pl, err := e.makePlan(ctx, base, work, p.Name(), opts)
 	if err != nil {
 		return nil, err
 	}
@@ -782,6 +795,7 @@ func (e *Engine) applyOps(ctx context.Context, cs *model.Changeset, reqs []Reque
 	}
 	res.ChangesetID = cs.ID
 	res.Applied = true
+	e.removeDerived(pl)
 	e.log.Info("changeset applied", "changeset", cs.ID, "user", p.Name(), "ops", len(cs.Ops), "files", len(res.Files), "description", cs.Description)
 	return res, nil
 }
@@ -956,15 +970,16 @@ func (e *Engine) Resync(ctx context.Context, p *auth.Principal, opts ApplyOption
 		return nil, err
 	}
 	work := base.Clone()
-	pl, err := e.makePlan(ctx, base, work, p.Name())
+	pl, err := e.makePlan(ctx, base, work, p.Name(), opts)
 	if err != nil {
 		return nil, err
 	}
 	res := pl.result()
 	res.DryRun = opts.DryRun
-	if validate.HasErrors(pl.existing) {
+	if validate.HasErrors(pl.existing) || validate.HasErrors(pl.introduced) {
 		// Resync deploys the stored state as is; it must be valid.
-		return res, &Error{Kind: KindValidation, Message: "the stored configuration has errors: " + describeErrors(pl.existing), Problems: validate.Errors(pl.existing)}
+		ps := append(append([]validate.Problem{}, pl.existing...), pl.introduced...)
+		return res, &Error{Kind: KindValidation, Message: "the stored configuration has errors: " + describeErrors(ps), Problems: validate.Errors(ps)}
 	}
 	if pl.check != nil && !pl.check.OK {
 		return res, &Error{Kind: KindValidation, Message: "named-checkconf rejected the configuration: " + firstCheckError(pl.checkMsgs), Check: pl.checkMsgs}
@@ -998,15 +1013,26 @@ func (e *Engine) Resync(ctx context.Context, p *auth.Principal, opts ApplyOption
 	}
 	deployed := deployedList(pl.out, 0, e.Now())
 	err = e.store.InTx(ctx, func(tx *store.Tx) error {
+		// Serials raised above named's (guardSerials) are kept.
+		if len(pl.serials) > 0 {
+			if err := tx.SaveState(base, work); err != nil {
+				return err
+			}
+		}
 		if err := tx.SetDeployedFiles(deployed); err != nil {
 			return err
 		}
-		return tx.AddAudit(e.auditEvent(p, "system.resync", "", 0, "", 0, "success", fmt.Sprintf("%d files written", len(res.Files)), nil))
+		var details json.RawMessage
+		if len(pl.serials) > 0 {
+			details, _ = json.Marshal(map[string]any{"serials": pl.serials})
+		}
+		return tx.AddAudit(e.auditEvent(p, "system.resync", "", 0, "", 0, "success", fmt.Sprintf("%d files written", len(res.Files)), details))
 	})
 	if err != nil {
 		return res, err
 	}
 	res.Applied = true
+	e.removeDerived(pl)
 	return res, nil
 }
 
@@ -1058,7 +1084,7 @@ func (e *Engine) CheckCurrent(ctx context.Context) (*Result, error) {
 	if err != nil {
 		return nil, err
 	}
-	pl, err := e.makePlan(ctx, base, base.Clone(), "")
+	pl, err := e.makePlan(ctx, base, base.Clone(), "", ApplyOptions{})
 	if err != nil {
 		return nil, err
 	}
@@ -1192,7 +1218,9 @@ func (e *Engine) WorkingState(ctx context.Context, csID int64, p *auth.Principal
 }
 
 // LoadedSerial returns the serial named serves for zone z, from rndc
-// zonestatus. ok is false when named isn't asked (no_reload) or doesn't
+// zonestatus: for a zone named signs, the signed zone's serial (which
+// secondaries and the rest of the world see), not that of the zone file
+// Jarl wrote. ok is false when named isn't asked (no_reload) or doesn't
 // report a serial (the zone isn't loaded yet).
 func (e *Engine) LoadedSerial(ctx context.Context, st *model.State, z *model.Zone) (serial uint32, ok bool, err error) {
 	if e.cfg.NoReload || e.tools == nil {
@@ -1202,5 +1230,6 @@ func (e *Engine) LoadedSerial(ctx context.Context, st *model.State, z *model.Zon
 	if err != nil {
 		return 0, false, err
 	}
-	return zs.Serial, zs.HasSerial, nil
+	serial, ok = zs.ServedSerial()
+	return serial, ok, nil
 }