Merge branch 'main' into v2

* main: chore(fs): speed up case normalization (#10013) chore(config): remove discontinued secondary STUN servers (fixes #10011) (#10012) chore(gui, man, authors): update docs, translations, and contributors fix(stun): better error handling (ref #10008) (#10010) fix(config): remove discontinued primary STUN server (fixes #10008) (#10009) fix(gui): validate device ID in canonical form (fixes #7291) (#10006)
2025-04-01 13:43:33 +02:00
parent a99e670ebb 05cc6b0f43
commit 2953630bc3
16 changed files with 135 additions and 67 deletions
@@ -71,22 +71,19 @@ var (

 	// DefaultPrimaryStunServers are servers provided by us (to avoid causing the public servers burden)
 	DefaultPrimaryStunServers = []string{
-		"stun.syncthing.net:3478",
+		// Discontinued because of misuse. See https://forum.syncthing.net/t/stun-server-misuse/23319
+		//"stun.syncthing.net:3478",
 	}
 	DefaultSecondaryStunServers = []string{
-		"stun.callwithus.com:3478",
 		"stun.counterpath.com:3478",
 		"stun.counterpath.net:3478",
 		"stun.ekiga.net:3478",
 		"stun.hitv.com:3478",
-		"stun.ideasip.com:3478",
 		"stun.internetcalls.com:3478",
 		"stun.miwifi.com:3478",
 		"stun.schlund.de:3478",
-		"stun.sipgate.net:10000",
 		"stun.sipgate.net:3478",
 		"stun.voip.aebc.com:3478",
-		"stun.voiparound.com:3478",
 		"stun.voipbuster.com:3478",
 		"stun.voipstunt.com:3478",
 		"stun.xten.com:3478",
@@ -17,6 +17,52 @@ import (
 // UnicodeLowercaseNormalized returns the Unicode lower case variant of s,
 // having also normalized it to normalization form C.
 func UnicodeLowercaseNormalized(s string) string {
+	if isASCII, isLower := isASCII(s); isASCII {
+		if isLower {
+			return s
+		}
+		return toLowerASCII(s)
+	}
+
+	return toLowerUnicode(s)
+}
+
+func isASCII(s string) (bool, bool) {
+	isLower := true
+	for _, b := range []byte(s) {
+		if b > unicode.MaxASCII {
+			return false, isLower
+		}
+		if 'A' <= b && b <= 'Z' {
+			isLower = false
+		}
+	}
+	return true, isLower
+}
+
+func toLowerASCII(s string) string {
+	var (
+		b   strings.Builder
+		pos int
+	)
+	b.Grow(len(s))
+	for i, c := range []byte(s) {
+		if c < 'A' || 'Z' < c {
+			continue
+		}
+		if pos < i {
+			b.WriteString(s[pos:i])
+		}
+		pos = i + 1
+		b.WriteByte(c + 'a' - 'A')
+	}
+	if pos != len(s) {
+		b.WriteString(s[pos:])
+	}
+	return b.String()
+}
+
+func toLowerUnicode(s string) string {
 	i := firstCaseChange(s)
 	if i == -1 {
 		return norm.NFC.String(s)
@@ -30,7 +76,11 @@ func UnicodeLowercaseNormalized(s string) string {
 	rs.WriteString(s[:i])

 	for _, r := range s[i:] {
-		rs.WriteRune(unicode.ToLower(unicode.ToUpper(r)))
+		if r <= unicode.MaxLatin1 && r != 'µ' {
+			rs.WriteRune(unicode.ToLower(r))
+		} else {
+			rs.WriteRune(unicode.To(unicode.LowerCase, unicode.To(unicode.UpperCase, r)))
+		}
 	}
 	return norm.NFC.String(rs.String())
 }
@@ -38,10 +88,13 @@ func UnicodeLowercaseNormalized(s string) string {
 // Byte index of the first rune r s.t. lower(upper(r)) != r.
 func firstCaseChange(s string) int {
 	for i, r := range s {
-		if r <= unicode.MaxASCII && (r < 'A' || r > 'Z') {
-			continue
+		if r <= unicode.MaxASCII {
+			if r < 'A' || r > 'Z' {
+				continue
+			}
+			return i
 		}
-		if unicode.ToLower(unicode.ToUpper(r)) != r {
+		if unicode.To(unicode.LowerCase, unicode.To(unicode.UpperCase, r)) != r {
 			return i
 		}
 	}
@@ -49,6 +49,18 @@ var caseCases = [][2]string{
 	{"a\xCC\x88", "\xC3\xA4"}, // ä
 }

+var benchmarkCases = [][2]string{
+	{"img_202401241010.jpg", "ASCII lowercase"},
+	{"IMG_202401241010.jpg", "ASCII mixedcase start"},
+	{"img_202401241010.JPG", "ASCII mixedcase end"},
+	{"wir_kinder_aus_bullerbü.epub", "Latin1 lowercase"},
+	{"Wir_Kinder_aus_Bullerbü.epub", "Latin1 mixedcase start"},
+	{"wir_kinder_aus_bullerbü.EPUB", "Latin1 mixedcase end"},
+	{"translated_ウェブの国際化.html", "Unicode lowercase"},
+	{"Translated_ウェブの国際化.html", "Unicode mixedcase start"},
+	{"translated_ウェブの国際化.HTML", "Unicode mixedcase end"},
+}
+
 func TestUnicodeLowercaseNormalized(t *testing.T) {
 	for _, tc := range caseCases {
 		res := UnicodeLowercaseNormalized(tc[0])
@@ -58,22 +70,13 @@ func TestUnicodeLowercaseNormalized(t *testing.T) {
 	}
 }

-func BenchmarkUnicodeLowercaseMaybeChange(b *testing.B) {
-	b.ReportAllocs()
-
-	for i := 0; i < b.N; i++ {
-		for _, s := range caseCases {
-			UnicodeLowercaseNormalized(s[0])
-		}
-	}
-}
-
-func BenchmarkUnicodeLowercaseNoChange(b *testing.B) {
-	b.ReportAllocs()
-
-	for i := 0; i < b.N; i++ {
-		for _, s := range caseCases {
-			UnicodeLowercaseNormalized(s[1])
-		}
+func BenchmarkUnicodeLowercase(b *testing.B) {
+	for _, c := range benchmarkCases {
+		b.Run(c[1], func(b *testing.B) {
+			b.ReportAllocs()
+			for i := 0; i < b.N; i++ {
+				UnicodeLowercaseNormalized(c[0])
+			}
+		})
 	}
 }
@@ -8,6 +8,8 @@ package stun

 import (
 	"context"
+	"errors"
+	"fmt"
 	"net"
 	"time"

@@ -38,6 +40,8 @@ const (
 	NATSymmetricUDPFirewall = stun.NATSymmetricUDPFirewall
 )

+var errNotPunchable = errors.New("not punchable")
+
 type Subscriber interface {
 	OnNATTypeChanged(natType NATType)
 	OnExternalAddressChanged(address *Host, via string)
@@ -110,10 +114,11 @@ func (s *Service) Serve(ctx context.Context) error {
 		l.Debugf("Starting stun for %s", s)

 		for _, addr := range s.cfg.Options().StunServers() {
-			// This blocks until we hit an exit condition or there are issues with the STUN server.
-			// This returns a boolean signifying if a different STUN server should be tried (oppose to the whole thing
-			// shutting down and this winding itself down.
-			s.runStunForServer(ctx, addr)
+			// This blocks until we hit an exit condition or there are
+			// issues with the STUN server.
+			if err := s.runStunForServer(ctx, addr); errors.Is(err, errNotPunchable) {
+				break // we will sleep for a while
+			}

 			// Have we been asked to stop?
 			select {
@@ -129,11 +134,6 @@ func (s *Service) Serve(ctx context.Context) error {
 				s.setExternalAddress(nil, "")
 				goto disabled
 			}
-
-			// Unpunchable NAT? Chillout for some time.
-			if !s.isCurrentNATTypePunchable() {
-				break
-			}
 		}

 		// We failed to contact all provided stun servers or the nat is not punchable.
@@ -142,7 +142,7 @@ func (s *Service) Serve(ctx context.Context) error {
 	}
 }

-func (s *Service) runStunForServer(ctx context.Context, addr string) {
+func (s *Service) runStunForServer(ctx context.Context, addr string) error {
 	l.Debugf("Running stun for %s via %s", s, addr)

 	// Resolve the address, so that in case the server advertises two
@@ -153,7 +153,7 @@ func (s *Service) runStunForServer(ctx context.Context, addr string) {
 	udpAddr, err := net.ResolveUDPAddr("udp", addr)
 	if err != nil {
 		l.Debugf("%s stun addr resolution on %s: %s", s, addr, err)
-		return
+		return err
 	}
 	s.client.SetServerAddr(udpAddr.String())

@@ -163,15 +163,18 @@ func (s *Service) runStunForServer(ctx context.Context, addr string) {
 		natType, extAddr, err = s.client.Discover()
 		return err
 	})
-	if err != nil || extAddr == nil {
-		l.Debugf("%s stun discovery on %s: %s", s, addr, err)
-		return
+	if err != nil {
+		l.Debugf("%s stun discovery on %s: %v", s, addr, err)
+		return err
+	} else if extAddr == nil {
+		l.Debugf("%s stun discovery on %s resulted in no address", s, addr)
+		return fmt.Errorf("%s: no address", addr)
 	}

 	// The stun server is most likely borked, try another one.
 	if natType == NATError || natType == NATUnknown || natType == NATBlocked {
 		l.Debugf("%s stun discovery on %s resolved to %s", s, addr, natType)
-		return
+		return fmt.Errorf("%s: bad result: %v", addr, natType)
 	}

 	s.setNATType(natType)
@@ -181,15 +184,14 @@ func (s *Service) runStunForServer(ctx context.Context, addr string) {
 	// and such, just let the caller check the nat type and work it out themselves.
 	if !s.isCurrentNATTypePunchable() {
 		l.Debugf("%s cannot punch %s, skipping", s, natType)
-		return
+		return errNotPunchable
 	}

 	s.setExternalAddress(extAddr, addr)
-
-	s.stunKeepAlive(ctx, addr, extAddr)
+	return s.stunKeepAlive(ctx, addr, extAddr)
 }

-func (s *Service) stunKeepAlive(ctx context.Context, addr string, extAddr *Host) {
+func (s *Service) stunKeepAlive(ctx context.Context, addr string, extAddr *Host) error {
 	var err error
 	nextSleep := time.Duration(s.cfg.Options().StunKeepaliveStartS) * time.Second

@@ -211,7 +213,7 @@ func (s *Service) stunKeepAlive(ctx context.Context, addr string, extAddr *Host)
 			minSleep := time.Duration(s.cfg.Options().StunKeepaliveMinS) * time.Second
 			if nextSleep < minSleep {
 				l.Debugf("%s keepalive aborting, sleep below min: %s < %s", s, nextSleep, minSleep)
-				return
+				return fmt.Errorf("unreasonably low keepalive: %v", minSleep)
 			}
 		}

@@ -238,13 +240,13 @@ func (s *Service) stunKeepAlive(ctx context.Context, addr string, extAddr *Host)
 		case <-time.After(sleepFor):
 		case <-ctx.Done():
 			l.Debugf("%s stopping, aborting stun", s)
-			return
+			return ctx.Err()
 		}

 		if s.cfg.Options().IsStunDisabled() {
 			// Disabled, give up
 			l.Debugf("%s disabled, aborting stun ", s)
-			return
+			return errors.New("disabled")
 		}

 		// Check if any writes happened while we were sleeping, if they did, sleep again
@@ -259,7 +261,7 @@ func (s *Service) stunKeepAlive(ctx context.Context, addr string, extAddr *Host)
 		extAddr, err = s.client.Keepalive()
 		if err != nil {
 			l.Debugf("%s stun keepalive on %s: %s (%v)", s, addr, err, extAddr)
-			return
+			return err
 		}
 		ourLastWrite = time.Now()
 	}