Add ServerInfo to resolvers and caches

resolver/namerecord.go

@@ -35,6 +35,7 @@ type NameRecord struct {
 
 	Server      string
 	ServerScope int8
+	ServerInfo  string
 }
 
 func makeNameRecordKey(domain string, question string) string {

resolver/resolver-env.go

@@ -23,6 +23,7 @@ var (
 		Server:        ServerSourceEnv,
 		ServerType:    ServerTypeEnv,
 		ServerIPScope: netutils.SiteLocal,
+		ServerInfo:    "Portmaster environment",
 		Source:        ServerSourceEnv,
 		Conn:          &envResolverConn{},
 	}
@@ -114,6 +115,7 @@ func (er *envResolverConn) makeRRCache(q *Query, answers []dns.RR) *RRCache {
 		Extra:       []dns.RR{internalSpecialUseComment}, // Always add comment about this TLD.
 		Server:      envResolver.Server,
 		ServerScope: envResolver.ServerIPScope,
+		ServerInfo:  envResolver.ServerInfo,
 	}
 }
 

resolver/resolver-mdns.go

@@ -34,6 +34,7 @@ var (
 		Server:        ServerSourceMDNS,
 		ServerType:    ServerTypeDNS,
 		ServerIPScope: netutils.SiteLocal,
+		ServerInfo:    "mDNS resolver",
 		Source:        ServerSourceMDNS,
 		Conn:          &mDNSResolverConn{},
 	}
@@ -203,6 +204,7 @@ func handleMDNSMessages(ctx context.Context, messages chan *dns.Msg) error {
 						Question:    dns.Type(question.Qtype),
 						Server:      mDNSResolver.Server,
 						ServerScope: mDNSResolver.ServerIPScope,
+						ServerInfo:  mDNSResolver.ServerInfo,
 					}
 				}
 			}
@@ -304,6 +306,7 @@ func handleMDNSMessages(ctx context.Context, messages chan *dns.Msg) error {
 					Answer:      []dns.RR{v},
 					Server:      mDNSResolver.Server,
 					ServerScope: mDNSResolver.ServerIPScope,
+					ServerInfo:  mDNSResolver.ServerInfo,
 				}
 				rrCache.Clean(minMDnsTTL)
 				err := rrCache.Save()
@@ -416,7 +419,14 @@ func queryMulticastDNS(ctx context.Context, q *Query) (*RRCache, error) {
 		}
 	}
 
-	return nil, ErrNotFound
+	// Respond with NXDomain.
+	return &RRCache{
+		Domain:      q.FQDN,
+		Question:    q.QType,
+		Server:      mDNSResolver.Server,
+		ServerScope: mDNSResolver.ServerIPScope,
+		ServerInfo:  mDNSResolver.ServerInfo,
+	}, nil
 }
 
 func cleanSavedQuestions() {

resolver/resolver-plain.go

@@ -86,6 +86,7 @@ func (pr *PlainResolver) Query(ctx context.Context, q *Query) (*RRCache, error)
 		Extra:       reply.Extra,
 		Server:      pr.resolver.Server,
 		ServerScope: pr.resolver.ServerIPScope,
+		ServerInfo:  pr.resolver.ServerInfo,
 	}
 
 	// TODO: check if reply.Answer is valid

resolver/resolver-tcp.go

@@ -51,6 +51,7 @@ func (ifq *InFlightQuery) MakeCacheRecord(reply *dns.Msg) *RRCache {
 		Extra:       reply.Extra,
 		Server:      ifq.Resolver.Server,
 		ServerScope: ifq.Resolver.ServerIPScope,
+		ServerInfo:  ifq.Resolver.ServerInfo,
 	}
 }
 

resolver/resolver.go

@@ -60,6 +60,7 @@ type Resolver struct {
 	ServerIP      net.IP
 	ServerIPScope int8
 	ServerPort    uint16
+	ServerInfo    string
 
 	// Special Options
 	VerifyDomain string

resolver/resolvers.go

@@ -128,6 +128,13 @@ func createResolver(resolverURL, source string) (*Resolver, bool, error) {
 		UpstreamBlockDetection: blockType,
 	}
 
+	u.RawQuery = "" // Remove options from parsed URL
+	if new.Name != "" {
+		new.ServerInfo = fmt.Sprintf("%s (%s, from %s)", new.Name, u, source)
+	} else {
+		new.ServerInfo = fmt.Sprintf("%s (from %s)", u, source)
+	}
+
 	new.Conn = resolverConnFactory(new)
 	return new, false, nil
 }

resolver/rrcache.go

@@ -1,6 +1,7 @@
 package resolver
 
 import (
+	"context"
 	"fmt"
 	"math/rand"
 	"net"
@@ -8,6 +9,7 @@ import (
 	"time"
 
 	"github.com/safing/portbase/log"
+	"github.com/safing/portmaster/nameserver/nsutil"
 	"github.com/safing/portmaster/netenv"
 
 	"github.com/miekg/dns"
@@ -130,6 +132,7 @@ func (rrCache *RRCache) ToNameRecord() *NameRecord {
 		TTL:         rrCache.TTL,
 		Server:      rrCache.Server,
 		ServerScope: rrCache.ServerScope,
+		ServerInfo:  rrCache.ServerInfo,
 	}
 
 	// stringify RR entries
@@ -176,6 +179,7 @@ func GetRRCache(domain string, question dns.Type) (*RRCache, error) {
 
 	rrCache.Server = nameRecord.Server
 	rrCache.ServerScope = nameRecord.ServerScope
+	rrCache.ServerInfo = nameRecord.ServerInfo
 	rrCache.servedFromCache = true
 	return rrCache, nil
 }
@@ -239,6 +243,7 @@ func (rrCache *RRCache) ShallowCopy() *RRCache {
 
 		Server:      rrCache.Server,
 		ServerScope: rrCache.ServerScope,
+		ServerInfo:  rrCache.ServerInfo,
 
 		updated:         rrCache.updated,
 		servedFromCache: rrCache.servedFromCache,