From 73470e8dd8d020f3f19d77545cce00a9dbb96c2e Mon Sep 17 00:00:00 2001 From: rurirei <72071920+rurirei@users.noreply.github.com> Date: Tue, 10 Aug 2021 10:49:56 +0800 Subject: [PATCH] DNS: fix typo & refine code (#1183) Co-authored-by: loyalsoldier <10487845+Loyalsoldier@users.noreply.github.com> --- app/dns/dnscommon.go | 2 +- app/dns/nameserver_doh.go | 47 +++++++++++++-------------- app/dns/nameserver_quic.go | 49 ++++++++++++++-------------- app/dns/nameserver_tcp.go | 53 +++++++++++++++--------------- app/dns/nameserver_udp.go | 66 ++++++++++++++++++++------------------ 5 files changed, 111 insertions(+), 106 deletions(-) diff --git a/app/dns/dnscommon.go b/app/dns/dnscommon.go index 239e04c2101..07907b1ba53 100644 --- a/app/dns/dnscommon.go +++ b/app/dns/dnscommon.go @@ -213,7 +213,7 @@ L: case dnsmessage.TypeAAAA: ans, err := parser.AAAAResource() if err != nil { - newError("failed to parse A record for domain: ", ah.Name).Base(err).WriteToLog() + newError("failed to parse AAAA record for domain: ", ah.Name).Base(err).WriteToLog() break L } ipRecord.IP = append(ipRecord.IP, net.IPAddress(ans.AAAA[:])) diff --git a/app/dns/nameserver_doh.go b/app/dns/nameserver_doh.go index 5b471ab65fa..3faec7e2cd5 100644 --- a/app/dns/nameserver_doh.go +++ b/app/dns/nameserver_doh.go @@ -32,7 +32,7 @@ import ( // thus most of the DOH implementation is copied from udpns.go type DoHNameServer struct { sync.RWMutex - ips map[string]record + ips map[string]*record pub *pubsub.Service cleanup *task.Periodic reqID uint32 @@ -112,7 +112,7 @@ func NewDoHLocalNameServer(url *url.URL) *DoHNameServer { func baseDOHNameServer(url *url.URL, prefix string) *DoHNameServer { s := &DoHNameServer{ - ips: make(map[string]record), + ips: make(map[string]*record), pub: pubsub.NewService(), name: prefix + "//" + url.Host, dohURL: url.String(), @@ -156,7 +156,7 @@ func (s *DoHNameServer) Cleanup() error { } if len(s.ips) == 0 { - s.ips = make(map[string]record) + s.ips = make(map[string]*record) } return nil @@ -166,7 +166,10 @@ func (s *DoHNameServer) updateIP(req *dnsRequest, ipRec *IPRecord) { elapsed := time.Since(req.start) s.Lock() - rec := s.ips[req.domain] + rec, found := s.ips[req.domain] + if !found { + rec = &record{} + } updated := false switch req.reqType { @@ -176,7 +179,7 @@ func (s *DoHNameServer) updateIP(req *dnsRequest, ipRec *IPRecord) { updated = true } case dnsmessage.TypeAAAA: - addr := make([]net.Address, 0) + addr := make([]net.Address, 0, len(ipRec.IP)) for _, ip := range ipRec.IP { if len(ip.IP()) == net.IPv6len { addr = append(addr, ip) @@ -295,34 +298,30 @@ func (s *DoHNameServer) findIPsForDomain(domain string, option dns_feature.IPOpt return nil, errRecordNotFound } + var err4 error + var err6 error var ips []net.Address - var lastErr error - if option.IPv6Enable && record.AAAA != nil && record.AAAA.RCode == dnsmessage.RCodeSuccess { - aaaa, err := record.AAAA.getIPs() - if err != nil { - lastErr = err - } - ips = append(ips, aaaa...) - } - - if option.IPv4Enable && record.A != nil && record.A.RCode == dnsmessage.RCodeSuccess { - a, err := record.A.getIPs() - if err != nil { - lastErr = err - } - ips = append(ips, a...) + var ip6 []net.Address + + switch { + case option.IPv4Enable: + ips, err4 = record.A.getIPs() + fallthrough + case option.IPv6Enable: + ip6, err6 = record.AAAA.getIPs() + ips = append(ips, ip6...) } if len(ips) > 0 { return toNetIP(ips) } - if lastErr != nil { - return nil, lastErr + if err4 != nil { + return nil, err4 } - if (option.IPv4Enable && record.A != nil) || (option.IPv6Enable && record.AAAA != nil) { - return nil, dns_feature.ErrEmptyResponse + if err6 != nil { + return nil, err6 } return nil, errRecordNotFound diff --git a/app/dns/nameserver_quic.go b/app/dns/nameserver_quic.go index 7854a5a3ea0..1394dc151a6 100644 --- a/app/dns/nameserver_quic.go +++ b/app/dns/nameserver_quic.go @@ -33,12 +33,12 @@ const handshakeIdleTimeout = time.Second * 8 // QUICNameServer implemented DNS over QUIC type QUICNameServer struct { sync.RWMutex - ips map[string]record + ips map[string]*record pub *pubsub.Service cleanup *task.Periodic reqID uint32 name string - destination net.Destination + destination *net.Destination session quic.Session } @@ -57,10 +57,10 @@ func NewQUICNameServer(url *url.URL) (*QUICNameServer, error) { dest := net.UDPDestination(net.DomainAddress(url.Hostname()), port) s := &QUICNameServer{ - ips: make(map[string]record), + ips: make(map[string]*record), pub: pubsub.NewService(), name: url.String(), - destination: dest, + destination: &dest, } s.cleanup = &task.Periodic{ Interval: time.Minute, @@ -102,7 +102,7 @@ func (s *QUICNameServer) Cleanup() error { } if len(s.ips) == 0 { - s.ips = make(map[string]record) + s.ips = make(map[string]*record) } return nil @@ -112,7 +112,10 @@ func (s *QUICNameServer) updateIP(req *dnsRequest, ipRec *IPRecord) { elapsed := time.Since(req.start) s.Lock() - rec := s.ips[req.domain] + rec, found := s.ips[req.domain] + if !found { + rec = &record{} + } updated := false switch req.reqType { @@ -232,34 +235,30 @@ func (s *QUICNameServer) findIPsForDomain(domain string, option dns_feature.IPOp return nil, errRecordNotFound } + var err4 error + var err6 error var ips []net.Address - var lastErr error - if option.IPv6Enable && record.AAAA != nil && record.AAAA.RCode == dnsmessage.RCodeSuccess { - aaaa, err := record.AAAA.getIPs() - if err != nil { - lastErr = err - } - ips = append(ips, aaaa...) - } - - if option.IPv4Enable && record.A != nil && record.A.RCode == dnsmessage.RCodeSuccess { - a, err := record.A.getIPs() - if err != nil { - lastErr = err - } - ips = append(ips, a...) + var ip6 []net.Address + + switch { + case option.IPv4Enable: + ips, err4 = record.A.getIPs() + fallthrough + case option.IPv6Enable: + ip6, err6 = record.AAAA.getIPs() + ips = append(ips, ip6...) } if len(ips) > 0 { return toNetIP(ips) } - if lastErr != nil { - return nil, lastErr + if err4 != nil { + return nil, err4 } - if (option.IPv4Enable && record.A != nil) || (option.IPv6Enable && record.AAAA != nil) { - return nil, dns_feature.ErrEmptyResponse + if err6 != nil { + return nil, err6 } return nil, errRecordNotFound diff --git a/app/dns/nameserver_tcp.go b/app/dns/nameserver_tcp.go index f3987afdd80..daee2d28a20 100644 --- a/app/dns/nameserver_tcp.go +++ b/app/dns/nameserver_tcp.go @@ -29,8 +29,8 @@ import ( type TCPNameServer struct { sync.RWMutex name string - destination net.Destination - ips map[string]record + destination *net.Destination + ips map[string]*record pub *pubsub.Service cleanup *task.Periodic reqID uint32 @@ -45,7 +45,7 @@ func NewTCPNameServer(url *url.URL, dispatcher routing.Dispatcher) (*TCPNameServ } s.dial = func(ctx context.Context) (net.Conn, error) { - link, err := dispatcher.Dispatch(ctx, s.destination) + link, err := dispatcher.Dispatch(ctx, *s.destination) if err != nil { return nil, err } @@ -67,7 +67,7 @@ func NewTCPLocalNameServer(url *url.URL) (*TCPNameServer, error) { } s.dial = func(ctx context.Context) (net.Conn, error) { - return internet.DialSystem(ctx, s.destination, nil) + return internet.DialSystem(ctx, *s.destination, nil) } return s, nil @@ -85,8 +85,8 @@ func baseTCPNameServer(url *url.URL, prefix string) (*TCPNameServer, error) { dest := net.TCPDestination(net.ParseAddress(url.Hostname()), port) s := &TCPNameServer{ - destination: dest, - ips: make(map[string]record), + destination: &dest, + ips: make(map[string]*record), pub: pubsub.NewService(), name: prefix + "//" + dest.NetAddr(), } @@ -130,7 +130,7 @@ func (s *TCPNameServer) Cleanup() error { } if len(s.ips) == 0 { - s.ips = make(map[string]record) + s.ips = make(map[string]*record) } return nil @@ -140,7 +140,10 @@ func (s *TCPNameServer) updateIP(req *dnsRequest, ipRec *IPRecord) { elapsed := time.Since(req.start) s.Lock() - rec := s.ips[req.domain] + rec, found := s.ips[req.domain] + if !found { + rec = &record{} + } updated := false switch req.reqType { @@ -274,30 +277,30 @@ func (s *TCPNameServer) findIPsForDomain(domain string, option dns_feature.IPOpt return nil, errRecordNotFound } + var err4 error + var err6 error var ips []net.Address - var lastErr error - if option.IPv4Enable { - a, err := record.A.getIPs() - if err != nil { - lastErr = err - } - ips = append(ips, a...) - } - - if option.IPv6Enable { - aaaa, err := record.AAAA.getIPs() - if err != nil { - lastErr = err - } - ips = append(ips, aaaa...) + var ip6 []net.Address + + switch { + case option.IPv4Enable: + ips, err4 = record.A.getIPs() + fallthrough + case option.IPv6Enable: + ip6, err6 = record.AAAA.getIPs() + ips = append(ips, ip6...) } if len(ips) > 0 { return toNetIP(ips) } - if lastErr != nil { - return nil, lastErr + if err4 != nil { + return nil, err4 + } + + if err6 != nil { + return nil, err6 } return nil, dns_feature.ErrEmptyResponse diff --git a/app/dns/nameserver_udp.go b/app/dns/nameserver_udp.go index 8fcc558ab65..c53609d3693 100644 --- a/app/dns/nameserver_udp.go +++ b/app/dns/nameserver_udp.go @@ -28,9 +28,9 @@ import ( type ClassicNameServer struct { sync.RWMutex name string - address net.Destination - ips map[string]record - requests map[uint16]dnsRequest + address *net.Destination + ips map[string]*record + requests map[uint16]*dnsRequest pub *pubsub.Service udpServer *udp.Dispatcher cleanup *task.Periodic @@ -45,9 +45,9 @@ func NewClassicNameServer(address net.Destination, dispatcher routing.Dispatcher } s := &ClassicNameServer{ - address: address, - ips: make(map[string]record), - requests: make(map[uint16]dnsRequest), + address: &address, + ips: make(map[string]*record), + requests: make(map[uint16]*dnsRequest), pub: pubsub.NewService(), name: strings.ToUpper(address.String()), } @@ -84,6 +84,7 @@ func (s *ClassicNameServer) Cleanup() error { } if record.A == nil && record.AAAA == nil { + newError(s.name, " cleanup ", domain).AtDebug().WriteToLog() delete(s.ips, domain) } else { s.ips[domain] = record @@ -91,7 +92,7 @@ func (s *ClassicNameServer) Cleanup() error { } if len(s.ips) == 0 { - s.ips = make(map[string]record) + s.ips = make(map[string]*record) } for id, req := range s.requests { @@ -101,7 +102,7 @@ func (s *ClassicNameServer) Cleanup() error { } if len(s.requests) == 0 { - s.requests = make(map[uint16]dnsRequest) + s.requests = make(map[uint16]*dnsRequest) } return nil @@ -139,15 +140,17 @@ func (s *ClassicNameServer) HandleResponse(ctx context.Context, packet *udp_prot elapsed := time.Since(req.start) newError(s.name, " got answer: ", req.domain, " ", req.reqType, " -> ", ipRec.IP, " ", elapsed).AtInfo().WriteToLog() if len(req.domain) > 0 && (rec.A != nil || rec.AAAA != nil) { - s.updateIP(req.domain, rec) + s.updateIP(req.domain, &rec) } } -func (s *ClassicNameServer) updateIP(domain string, newRec record) { +func (s *ClassicNameServer) updateIP(domain string, newRec *record) { s.Lock() - newError(s.name, " updating IP records for domain:", domain).AtDebug().WriteToLog() - rec := s.ips[domain] + rec, found := s.ips[domain] + if !found { + rec = &record{} + } updated := false if isNewer(rec.A, newRec.A) { @@ -160,6 +163,7 @@ func (s *ClassicNameServer) updateIP(domain string, newRec record) { } if updated { + newError(s.name, " updating IP records for domain:", domain).AtDebug().WriteToLog() s.ips[domain] = rec } if newRec.A != nil { @@ -182,7 +186,7 @@ func (s *ClassicNameServer) addPendingRequest(req *dnsRequest) { id := req.msg.ID req.expire = time.Now().Add(time.Second * 8) - s.requests[id] = *req + s.requests[id] = req } func (s *ClassicNameServer) sendQuery(ctx context.Context, domain string, clientIP net.IP, option dns_feature.IPOption) { @@ -200,7 +204,7 @@ func (s *ClassicNameServer) sendQuery(ctx context.Context, domain string, client udpCtx = session.ContextWithContent(udpCtx, &session.Content{ Protocol: "dns", }) - s.udpServer.Dispatch(udpCtx, s.address, b) + s.udpServer.Dispatch(udpCtx, *s.address, b) } } @@ -213,30 +217,30 @@ func (s *ClassicNameServer) findIPsForDomain(domain string, option dns_feature.I return nil, errRecordNotFound } + var err4 error + var err6 error var ips []net.Address - var lastErr error - if option.IPv4Enable { - a, err := record.A.getIPs() - if err != nil { - lastErr = err - } - ips = append(ips, a...) - } - - if option.IPv6Enable { - aaaa, err := record.AAAA.getIPs() - if err != nil { - lastErr = err - } - ips = append(ips, aaaa...) + var ip6 []net.Address + + switch { + case option.IPv4Enable: + ips, err4 = record.A.getIPs() + fallthrough + case option.IPv6Enable: + ip6, err6 = record.AAAA.getIPs() + ips = append(ips, ip6...) } if len(ips) > 0 { return toNetIP(ips) } - if lastErr != nil { - return nil, lastErr + if err4 != nil { + return nil, err4 + } + + if err6 != nil { + return nil, err6 } return nil, dns_feature.ErrEmptyResponse