Mark signed zones with a padlock, and name clients in statistics

The zones list shows a padlock after signed zones, linking to their
DNSSEC tab. Client lists in the statistics show the host name Jarl's
records have for each address (PTR, else A/AAAA); no DNS queries.

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

internal/server/h_stats.go

@@ -2,10 +2,14 @@ package server
 
 import (
 	"net/http"
+	"net/netip"
+	"slices"
 	"strings"
 	"time"
 
 	"jarl/internal/auth"
+	"jarl/internal/dnsname"
+	"jarl/internal/model"
 	"jarl/internal/stats"
 )
 
@@ -53,6 +57,9 @@ func (s *Server) statsSummary(w http.ResponseWriter, r *http.Request, p *auth.Pr
 	if err != nil {
 		return err
 	}
+	if err := s.nameClients(r, p, sum.Tops[stats.KindClient]); err != nil {
+		return err
+	}
 	writeJSON(w, http.StatusOK, sum)
 	return nil
 }
@@ -75,6 +82,11 @@ func (s *Server) statsTop(w http.ResponseWriter, r *http.Request, p *auth.Princi
 	if err != nil {
 		return badRequest("%v", err)
 	}
+	if kind == stats.KindClient || kind == stats.KindRefused {
+		if err := s.nameClients(r, p, es); err != nil {
+			return err
+		}
+	}
 	writeJSON(w, http.StatusOK, es)
 	return nil
 }
@@ -145,3 +157,86 @@ func (s *Server) statsBreakdown(w http.ResponseWriter, r *http.Request, p *auth.
 	writeJSON(w, http.StatusOK, es)
 	return nil
 }
+
+// nameClients gives client entries the host name Jarl's records have for
+// the address: the PTR record's target, or else the name of an A/AAAA
+// record with the address. It sends no DNS queries, and uses only records
+// the user may read. Anonymized clients (prefixes) get no name.
+func (s *Server) nameClients(r *http.Request, p *auth.Principal, es []stats.Entry) error {
+	if len(es) == 0 {
+		return nil
+	}
+	want := map[netip.Addr]bool{}
+	for _, e := range es {
+		if a, err := netip.ParseAddr(e.Key); err == nil {
+			want[a.Unmap()] = true
+		}
+	}
+	if len(want) == 0 {
+		return nil
+	}
+	st, err := s.state(r)
+	if err != nil {
+		return err
+	}
+	names := clientNames(st, want, func(rec *model.Record) bool { return canReadRecord(p, st, rec) })
+	for i, e := range es {
+		if a, err := netip.ParseAddr(e.Key); err == nil {
+			es[i].Name = names[a.Unmap()]
+		}
+	}
+	return nil
+}
+
+// clientNames finds names for the addresses in want (see nameClients).
+// Where several records match, the first in name order wins.
+func clientNames(st *model.State, want map[netip.Addr]bool, readable func(*model.Record) bool) map[netip.Addr]string {
+	ptr, host := map[netip.Addr]string{}, map[netip.Addr]string{}
+	var recs []*model.Record
+	for _, rec := range st.Records {
+		if !rec.Disabled && (rec.Type == "PTR" || rec.Type == "A" || rec.Type == "AAAA") {
+			recs = append(recs, rec)
+		}
+	}
+	slices.SortFunc(recs, func(a, b *model.Record) int {
+		if a.Name != b.Name {
+			if model.CanonicalLess(a.Name, b.Name) {
+				return -1
+			}
+			return 1
+		}
+		return strings.Compare(a.Data, b.Data)
+	})
+	for _, rec := range recs {
+		var a netip.Addr
+		var name string
+		if rec.Type == "PTR" {
+			var ok bool
+			if a, ok = dnsname.AddrFromReverse(rec.Name); !ok {
+				continue
+			}
+			name = rec.Data
+		} else {
+			var err error
+			if a, err = netip.ParseAddr(rec.Data); err != nil {
+				continue
+			}
+			name = rec.Name
+		}
+		a = a.Unmap()
+		m := host
+		if rec.Type == "PTR" {
+			m = ptr
+		}
+		if !want[a] || m[a] != "" || !readable(rec) {
+			continue
+		}
+		m[a] = dnsname.Display(name)
+	}
+	for a, n := range host {
+		if ptr[a] == "" {
+			ptr[a] = n
+		}
+	}
+	return ptr
+}