Give every view a TSIG key that selects it

Each view's match-clients starts with "key jarl-view-NAME" (after
"!key" for the views listed after it), so a query signed with a view's
key lands in that view from any address. The secrets are derived from a
random seed in Jarl's database. The delegation check signs its queries
to this server's own addresses with the key of the zone's view: before,
they got whichever view matched the server's address, usually internal.
jarl view key / GET /views/{id}/key show a key for dig -k (tsig:write,
audited). jarl-view- key names are reserved; the importer drops view
keys from a configuration Jarl wrote.

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

internal/importer/importer.go

@@ -393,6 +393,10 @@ func (im *importer) key(s *namedconf.Stmt) error {
 		return fmt.Errorf("%s: key without a block", s.Pos)
 	}
 	name := model.NormalizeKeyName(s.Arg(0))
+	if strings.HasPrefix(name, model.ViewKeyPrefix) {
+		// A view key from a configuration Jarl wrote: Jarl makes its own.
+		return nil
+	}
 	alg, secret := "", ""
 	if a := namedconf.FindOne(b.Stmts, "algorithm"); a != nil {
 		alg = strings.ToLower(a.Arg(0))
@@ -433,7 +437,7 @@ func (im *importer) view(s *namedconf.Stmt) error {
 		switch kw := st.Keyword(); kw {
 		case "match-clients":
 			if mb := st.FirstBlock(); mb != nil {
-				v.MatchClients = nonNil(elementStrings(mb))
+				v.MatchClients = withoutViewKeys(nonNil(elementStrings(mb)))
 			}
 		case "match-destinations":
 			if mb := st.FirstBlock(); mb != nil {
@@ -807,3 +811,23 @@ func allowsNone(o *namedconf.Stmt) bool {
 	}
 	return true
 }
+
+// withoutViewKeys drops the view keys Jarl puts in front of match-clients
+// (render/viewkeys.go) from a list read from a configuration Jarl wrote,
+// and the "any" it adds after them to a view that had no list.
+func withoutViewKeys(elems []string) []string {
+	out := []string{}
+	dropped := false
+	for _, e := range elems {
+		f := strings.Fields(strings.TrimPrefix(strings.TrimSpace(e), "!"))
+		if len(f) == 2 && f[0] == "key" && strings.HasPrefix(strings.Trim(f[1], `"`), model.ViewKeyPrefix) {
+			dropped = true
+			continue
+		}
+		out = append(out, e)
+	}
+	if dropped && len(out) == 1 && out[0] == "any" {
+		return []string{}
+	}
+	return out
+}