Update changelog

No need to extract it again when the url package provides it for us:
```
$ jq -n '{"AdminListen":"unix:///tmp/ygg.sock"}' | ./yggdrasil -useconf | grep 'admin socket'
2024/10/08 22:41:11 UNIX admin socket listening on /tmp/ygg.sock
```

Follow-up on #1176

.github/workflows/ci.yml

@@ -17,10 +17,10 @@ jobs:
     steps:
       - uses: actions/setup-go@v5
         with:
-          go-version: 1.21
+          go-version: stable
       - uses: actions/checkout@v4
       - name: golangci-lint
-        uses: golangci/golangci-lint-action@v3
+        uses: golangci/golangci-lint-action@v6
         with:
           args: --issues-exit-code=1
 
@@ -51,7 +51,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        goversion: ["1.21", "1.22"]
+        goversion: ["1.21", "1.22", "1.23"]
 
     name: Build & Test (Linux, Go ${{ matrix.goversion }})
     needs: [lint]
@@ -75,7 +75,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        goversion: ["1.21", "1.22"]
+        goversion: ["1.21", "1.22", "1.23"]
 
     name: Build & Test (Windows, Go ${{ matrix.goversion }})
     needs: [lint]
@@ -99,7 +99,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        goversion: ["1.21", "1.22"]
+        goversion: ["1.21", "1.22", "1.23"]
 
     name: Build & Test (macOS, Go ${{ matrix.goversion }})
     needs: [lint]
@@ -123,7 +123,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        goversion: ["1.21", "1.22"]
+        goversion: ["1.21", "1.22", "1.23"]
         goos:
           - freebsd
           - openbsd

.golangci.yml

@@ -2,9 +2,10 @@ run:
   build-tags:
     - lint
   issues-exit-code: 0 # TODO: change this to 1 when we want it to fail builds
-  skip-dirs:
+issues:
+  exclude-dirs:
     - contrib/
     - misc/
 linters:
   disable:
-    - gocyclo
+    - gocyclo

CHANGELOG.md

@@ -26,6 +26,31 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - in case of vulnerabilities.
 -->
 
+## [0.5.9] - 2024-10-19
+
+### Added
+
+* New command line option `-user` for changing the process UID/GID
+
+### Changed
+
+* The routing algorithm has been updated with RTT-aware link costing, which should prefer lower latency links over higher latency links where possible
+  * The calculated cost is an average of the link RTT, but newly established links are costed higher to begin with, such that unstable peerings can be avoided
+  * Link costs are only used where multiple next-hops are available and will be ignored if there is only one loop-free path to the destination
+  * This is protocol-compatible with existing v0.5.x nodes but will have the best results when peering with nodes that are also running the latest version
+  * The `getPeers` endpoint will now report the calculated link cost for each given peer
+* Upgrade dependencies
+
+### Fixed
+
+* Multicast discovery should now work again when building Yggdrasil as an Android framework
+* Multicast discovery will now correctly ignore interfaces that are not marked as running
+* Ephemeral links, such as those added by multicast, will no longer try to reconnect in a fast loop, fixing a high CPU issue
+* The TUN interface will no longer stop working when hitting a segment read error from vectorised reads
+* The `AllowedPublicKeys` option will once again no longer apply to multicast peerings, as was originally intended
+* A potential panic when shutting down peering links has been fixed
+* A redundant system call for setting MTU on OpenBSD has been removed
+
 ## [0.5.8] - 2024-08-12
 
 ### Fixed

cmd/yggdrasil/chuser_other.go

@@ -0,0 +1,10 @@
+//go:build !aix && !darwin && !dragonfly && !freebsd && !linux && !netbsd && !openbsd && !solaris
+// +build !aix,!darwin,!dragonfly,!freebsd,!linux,!netbsd,!openbsd,!solaris
+
+package main
+
+import "errors"
+
+func chuser(user string) error {
+	return errors.New("setting uid/gid is not supported on this platform")
+}

cmd/yggdrasil/chuser_unix.go

@@ -0,0 +1,87 @@
+//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
+// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris
+
+package main
+
+import (
+	"errors"
+	"fmt"
+	"math"
+	osuser "os/user"
+	"strconv"
+	"strings"
+	"syscall"
+)
+
+func chuser(user string) error {
+	group := ""
+	if i := strings.IndexByte(user, ':'); i >= 0 {
+		user, group = user[:i], user[i+1:]
+	}
+
+	u := (*osuser.User)(nil)
+	g := (*osuser.Group)(nil)
+
+	if user != "" {
+		if _, err := strconv.ParseUint(user, 10, 32); err == nil {
+			u, err = osuser.LookupId(user)
+			if err != nil {
+				return fmt.Errorf("failed to lookup user by id %q: %v", user, err)
+			}
+		} else {
+			u, err = osuser.Lookup(user)
+			if err != nil {
+				return fmt.Errorf("failed to lookup user by name %q: %v", user, err)
+			}
+		}
+	}
+	if group != "" {
+		if _, err := strconv.ParseUint(group, 10, 32); err == nil {
+			g, err = osuser.LookupGroupId(group)
+			if err != nil {
+				return fmt.Errorf("failed to lookup group by id %q: %v", user, err)
+			}
+		} else {
+			g, err = osuser.LookupGroup(group)
+			if err != nil {
+				return fmt.Errorf("failed to lookup group by name %q: %v", user, err)
+			}
+		}
+	}
+
+	if g != nil {
+		gid, _ := strconv.ParseUint(g.Gid, 10, 32)
+		var err error
+		if gid < math.MaxInt {
+			err = syscall.Setgid(int(gid))
+		} else {
+			err = errors.New("gid too big")
+		}
+
+		if err != nil {
+			return fmt.Errorf("failed to setgid %d: %v", gid, err)
+		}
+	} else if u != nil {
+		gid, _ := strconv.ParseUint(u.Gid, 10, 32)
+		err := syscall.Setgid(int(uint32(gid)))
+		if err != nil {
+			return fmt.Errorf("failed to setgid %d: %v", gid, err)
+		}
+	}
+
+	if u != nil {
+		uid, _ := strconv.ParseUint(u.Uid, 10, 32)
+		var err error
+		if uid < math.MaxInt {
+			err = syscall.Setuid(int(uid))
+		} else {
+			err = errors.New("uid too big")
+		}
+
+		if err != nil {
+			return fmt.Errorf("failed to setuid %d: %v", uid, err)
+		}
+	}
+
+	return nil
+}

cmd/yggdrasil/main.go

@@ -52,11 +52,12 @@ func main() {
 	getsnet := flag.Bool("subnet", false, "use in combination with either -useconf or -useconffile, outputs your IPv6 subnet")
 	getpkey := flag.Bool("publickey", false, "use in combination with either -useconf or -useconffile, outputs your public key")
 	loglevel := flag.String("loglevel", "info", "loglevel to enable")
+	chuserto := flag.String("user", "", "user (and, optionally, group) to set UID/GID to")
 	flag.Parse()
-	
+
 	done := make(chan struct{})
 	defer close(done)
-	
+
 	// Catch interrupts from the operating system to exit gracefully.
 	ctx, cancel := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
 
@@ -271,7 +272,7 @@ func main() {
 			n.tun.SetupAdminHandlers(n.admin)
 		}
 	}
-	
+
 	//Windows service shutdown
 	minwinsvc.SetOnExit(func() {
 		logger.Infof("Shutting down service ...")
@@ -280,6 +281,14 @@ func main() {
 		<-done
 	})
 
+	// Change user if requested
+	if *chuserto != "" {
+		err = chuser(*chuserto)
+		if err != nil {
+			panic(err)
+		}
+	}
+
 	// Block until we are told to shut down.
 	<-ctx.Done()
 

cmd/yggdrasilctl/cmd_line_env.go

@@ -38,7 +38,6 @@ func (cmdLineEnv *CmdLineEnv) parseFlagsAndArgs() {
 		fmt.Println("Examples:")
 		fmt.Println("  - ", os.Args[0], "list")
 		fmt.Println("  - ", os.Args[0], "getPeers")
-		fmt.Println("  - ", os.Args[0], "setTunTap name=auto mtu=1500 tap_mode=false")
 		fmt.Println("  - ", os.Args[0], "-endpoint=tcp://localhost:9001 getPeers")
 		fmt.Println("  - ", os.Args[0], "-endpoint=unix:///var/run/ygg.sock getPeers")
 	}

cmd/yggdrasilctl/main.go

@@ -174,7 +174,7 @@ func run() int {
 		if err := json.Unmarshal(recv.Response, &resp); err != nil {
 			panic(err)
 		}
-		table.SetHeader([]string{"URI", "State", "Dir", "IP Address", "Uptime", "RTT", "RX", "TX", "Pr", "Last Error"})
+		table.SetHeader([]string{"URI", "State", "Dir", "IP Address", "Uptime", "RTT", "RX", "TX", "Pr", "Cost", "Last Error"})
 		for _, peer := range resp.Peers {
 			state, lasterr, dir, rtt := "Up", "-", "Out", "-"
 			if !peer.Up {
@@ -200,6 +200,7 @@ func run() int {
 				peer.RXBytes.String(),
 				peer.TXBytes.String(),
 				fmt.Sprintf("%d", peer.Priority),
+				fmt.Sprintf("%d", peer.Cost),
 				lasterr,
 			})
 		}

contrib/mobile/build

@@ -7,6 +7,7 @@ set -ef
 PKGSRC=${PKGSRC:-github.com/yggdrasil-network/yggdrasil-go/src/version}
 PKGNAME=${PKGNAME:-$(sh contrib/semver/name.sh)}
 PKGVER=${PKGVER:-$(sh contrib/semver/version.sh --bare)}
+GOVER=$(go version | { read _ _ version _; echo ${version#go}; })
 
 LDFLAGS="-X $PKGSRC.buildName=$PKGNAME -X $PKGSRC.buildVersion=$PKGVER"
 ARGS="-v"
@@ -33,6 +34,15 @@ if [ ! $IOS ] && [ ! $ANDROID ]; then
   exit 1
 fi
 
+ver_le() {
+    printf "$1\n$2\n" | sort -VC
+}
+
+if [ $ANDROID ] && ver_le 1.23.0 $GOVER ; then
+    # github.com/wlynxg/anet library relies on //go:linkname
+    LDFLAGS="$LDFLAGS -checklinkname=0"
+fi
+
 if [ $IOS ]; then
   echo "Building framework for iOS"
   go get golang.org/x/mobile/bind

contrib/mobile/mobile.go

@@ -15,8 +15,6 @@ import (
 	"github.com/yggdrasil-network/yggdrasil-go/src/multicast"
 	"github.com/yggdrasil-network/yggdrasil-go/src/tun"
 	"github.com/yggdrasil-network/yggdrasil-go/src/version"
-
-	_ "golang.org/x/mobile/bind"
 )
 
 // Yggdrasil mobile package is meant to "plug the gap" for mobile support, as

go.mod

@@ -3,23 +3,24 @@ module github.com/yggdrasil-network/yggdrasil-go
 go 1.21
 
 require (
-	github.com/Arceliar/ironwood v0.0.0-20240529054413-b8e59574e2b2
+	github.com/Arceliar/ironwood v0.0.0-20241016082300-f6fb9da97a17
 	github.com/Arceliar/phony v0.0.0-20220903101357-530938a4b13d
 	github.com/cheggaaa/pb/v3 v3.1.5
+	github.com/coder/websocket v1.8.12
 	github.com/gologme/log v1.3.0
 	github.com/hashicorp/go-syslog v1.0.0
 	github.com/hjson/hjson-go/v4 v4.4.0
 	github.com/kardianos/minwinsvc v1.0.2
-	github.com/quic-go/quic-go v0.45.1
-	github.com/vishvananda/netlink v1.1.0
-	golang.org/x/crypto v0.25.0
-	golang.org/x/mobile v0.0.0-20240716161057-1ad2df20a8b6
-	golang.org/x/net v0.27.0
-	golang.org/x/sys v0.22.0
-	golang.org/x/text v0.16.0
+	github.com/quic-go/quic-go v0.46.0
+	github.com/vishvananda/netlink v1.3.0
+	github.com/wlynxg/anet v0.0.5
+	golang.org/x/crypto v0.28.0
+	golang.org/x/net v0.30.0
+	golang.org/x/sys v0.26.0
+	golang.org/x/text v0.19.0
+	golang.zx2c4.com/wintun v0.0.0-20230126152724-0fa3db229ce2
 	golang.zx2c4.com/wireguard v0.0.0-20231211153847-12269c276173
 	golang.zx2c4.com/wireguard/windows v0.5.3
-	nhooyr.io/websocket v1.8.11
 )
 
 require (
@@ -33,9 +34,8 @@ require (
 	go.uber.org/mock v0.4.0 // indirect
 	golang.org/x/exp v0.0.0-20240719175910-8a7402abbf56 // indirect
 	golang.org/x/mod v0.19.0 // indirect
-	golang.org/x/sync v0.7.0 // indirect
+	golang.org/x/sync v0.8.0 // indirect
 	golang.org/x/tools v0.23.0 // indirect
-	golang.zx2c4.com/wintun v0.0.0-20230126152724-0fa3db229ce2 // indirect
 )
 
 require (
@@ -44,5 +44,5 @@ require (
 	github.com/mattn/go-isatty v0.0.19 // indirect
 	github.com/mattn/go-runewidth v0.0.15 // indirect
 	github.com/olekukonko/tablewriter v0.0.5
-	github.com/vishvananda/netns v0.0.0-20210104183010-2eb08e3e575f // indirect
+	github.com/vishvananda/netns v0.0.4 // indirect
 )

go.sum

@@ -1,5 +1,5 @@
-github.com/Arceliar/ironwood v0.0.0-20240529054413-b8e59574e2b2 h1:SBdYBKeXYUUFef5wi2CMhYmXFVGiYaRpTvbki0Bu+JQ=
-github.com/Arceliar/ironwood v0.0.0-20240529054413-b8e59574e2b2/go.mod h1:6WP4799FX0OuWdENGQAh+0RXp9FLh0y7NZ7tM9cJyXk=
+github.com/Arceliar/ironwood v0.0.0-20241016082300-f6fb9da97a17 h1:uOvHqPwu09ndYZQDUL6QvyDcz0M9kwooKYa/PEfLwIU=
+github.com/Arceliar/ironwood v0.0.0-20241016082300-f6fb9da97a17/go.mod h1:6WP4799FX0OuWdENGQAh+0RXp9FLh0y7NZ7tM9cJyXk=
 github.com/Arceliar/phony v0.0.0-20220903101357-530938a4b13d h1:UK9fsWbWqwIQkMCz1CP+v5pGbsGoWAw6g4AyvMpm1EM=
 github.com/Arceliar/phony v0.0.0-20220903101357-530938a4b13d/go.mod h1:BCnxhRf47C/dy/e/D2pmB8NkB3dQVIrkD98b220rx5Q=
 github.com/VividCortex/ewma v1.2.0 h1:f58SaIzcDXrSy3kWaHNvuJgJ3Nmz59Zji6XoJR/q1ow=
@@ -14,6 +14,8 @@ github.com/cheggaaa/pb/v3 v3.1.5/go.mod h1:CrxkeghYTXi1lQBEI7jSn+3svI3cuc19haAj6
 github.com/chzyer/logex v1.1.10/go.mod h1:+Ywpsq7O8HXn0nuIou7OrIPyXbp3wmkHB+jjWRnGsAI=
 github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e/go.mod h1:nSuG5e5PlCu98SY8svDHJxuZscDgtXS6KTTbou5AhLI=
 github.com/chzyer/test v0.0.0-20180213035817-a1ea475d72b1/go.mod h1:Q3SI9o4m/ZMnBNeIyt5eFwwo7qiLfzFZmjNmxjkiQlU=
+github.com/coder/websocket v1.8.12 h1:5bUXkEPPIbewrnkU8LTCLVaxi4N4J8ahufH2vlo4NAo=
+github.com/coder/websocket v1.8.12/go.mod h1:LNVeNrXQZfe5qhS9ALED3uA+l5pPqvwXg3CKoDBB2gs=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
@@ -56,8 +58,8 @@ github.com/onsi/gomega v1.27.6 h1:ENqfyGeS5AX/rlXDd/ETokDz93u0YufY1Pgxuy/PvWE=
 github.com/onsi/gomega v1.27.6/go.mod h1:PIQNjfQwkP3aQAH7lf7j87O/5FiNr+ZR8+ipb+qQlhg=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/quic-go/quic-go v0.45.1 h1:tPfeYCk+uZHjmDRwHHQmvHRYL2t44ROTujLeFVBmjCA=
-github.com/quic-go/quic-go v0.45.1/go.mod h1:1dLehS7TIR64+vxGR70GDcatWTOtMX2PUtnKsjbTurI=
+github.com/quic-go/quic-go v0.46.0 h1:uuwLClEEyk1DNvchH8uCByQVjo3yKL9opKulExNDs7Y=
+github.com/quic-go/quic-go v0.46.0/go.mod h1:1dLehS7TIR64+vxGR70GDcatWTOtMX2PUtnKsjbTurI=
 github.com/rivo/uniseg v0.2.0 h1:S1pD9weZBuJdFmowNwbpi7BJ8TNftyUImj/0WQi72jY=
 github.com/rivo/uniseg v0.2.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
@@ -65,11 +67,12 @@ github.com/stretchr/testify v1.6.1 h1:hDPOHmpOpP40lSULcqw7IrRb/u7w6RpDC9399XyoNd
 github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/twmb/murmur3 v1.1.6 h1:mqrRot1BRxm+Yct+vavLMou2/iJt0tNVTTC0QoIjaZg=
 github.com/twmb/murmur3 v1.1.6/go.mod h1:Qq/R7NUyOfr65zD+6Q5IHKsJLwP7exErjN6lyyq3OSQ=
-github.com/vishvananda/netlink v1.1.0 h1:1iyaYNBLmP6L0220aDnYQpo1QEV4t4hJ+xEEhhJH8j0=
-github.com/vishvananda/netlink v1.1.0/go.mod h1:cTgwzPIzzgDAYoQrMm0EdrjRUBkTqKYppBueQtXaqoE=
-github.com/vishvananda/netns v0.0.0-20191106174202-0a2b9b5464df/go.mod h1:JP3t17pCcGlemwknint6hfoeCVQrEMVwxRLRjXpq+BU=
-github.com/vishvananda/netns v0.0.0-20210104183010-2eb08e3e575f h1:p4VB7kIXpOQvVn1ZaTIVp+3vuYAXFe3OJEvjbUYJLaA=
-github.com/vishvananda/netns v0.0.0-20210104183010-2eb08e3e575f/go.mod h1:DD4vA1DwXk04H54A1oHXtwZmA0grkVMdPxx/VGLCah0=
+github.com/vishvananda/netlink v1.3.0 h1:X7l42GfcV4S6E4vHTsw48qbrV+9PVojNfIhZcwQdrZk=
+github.com/vishvananda/netlink v1.3.0/go.mod h1:i6NetklAujEcC6fK0JPjT8qSwWyO0HLn4UKG+hGqeJs=
+github.com/vishvananda/netns v0.0.4 h1:Oeaw1EM2JMxD51g9uhtC0D7erkIjgmj8+JZc26m1YX8=
+github.com/vishvananda/netns v0.0.4/go.mod h1:SpkAiCQRtJ6TvvxPnOSyH3BMl6unz3xZlaprSwhNNJM=
+github.com/wlynxg/anet v0.0.5 h1:J3VJGi1gvo0JwZ/P1/Yc/8p63SoW98B5dHkYDmpgvvU=
+github.com/wlynxg/anet v0.0.5/go.mod h1:eay5PRQr7fIVAMbTbchTnO9gG65Hg/uYGdc7mguHxoA=
 github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
 go.uber.org/mock v0.4.0 h1:VcM4ZOtdbR4f6VXfiOpwpVJDL6lCReaZ6mw31wqh7KU=
 go.uber.org/mock v0.4.0/go.mod h1:a6FSlNadKUHUa9IP5Vyt1zh4fC7uAwxMutEAscFbkZc=
@@ -77,12 +80,10 @@ golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACk
 golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
 golang.org/x/crypto v0.19.0/go.mod h1:Iy9bg/ha4yyC70EfRS8jz+B6ybOBKMaSxLj6P6oBDfU=
 golang.org/x/crypto v0.23.0/go.mod h1:CKFgDieR+mRhux2Lsu27y0fO304Db0wZe70UKqHu0v8=
-golang.org/x/crypto v0.25.0 h1:ypSNr+bnYL2YhwoMt2zPxHFmbAN1KZs/njMG3hxUp30=
-golang.org/x/crypto v0.25.0/go.mod h1:T+wALwcMOSE0kXgUAnPAHqTLW+XHgcELELW8VaDgm/M=
+golang.org/x/crypto v0.28.0 h1:GBDwsMXVQi34v5CCYUm2jkJvu4cbtru2U4TN2PSyQnw=
+golang.org/x/crypto v0.28.0/go.mod h1:rmgy+3RHxRZMyY0jjAJShp2zgEdOqj2AO7U0pYmeQ7U=
 golang.org/x/exp v0.0.0-20240719175910-8a7402abbf56 h1:2dVuKD2vS7b0QIHQbpyTISPd0LeHDbnYEryqj5Q1ug8=
 golang.org/x/exp v0.0.0-20240719175910-8a7402abbf56/go.mod h1:M4RDyNAINzryxdtnbRXRL/OHtkFuWGRjvuhBJpk2IlY=
-golang.org/x/mobile v0.0.0-20240716161057-1ad2df20a8b6 h1:/VlmIrkuLf2wzPjkZ8imSpckHoW7Y71h66dxbLHSpi8=
-golang.org/x/mobile v0.0.0-20240716161057-1ad2df20a8b6/go.mod h1:TCsc78+c4cqb8IKEosz2LwJ6YRNkIjMuAYeHYjchGDE=
 golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
 golang.org/x/mod v0.8.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
 golang.org/x/mod v0.19.0 h1:fEdghXQSo20giMthA7cd28ZC+jts4amQ3YMXiP5oMQ8=
@@ -93,29 +94,29 @@ golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug
 golang.org/x/net v0.6.0/go.mod h1:2Tu9+aMcznHK/AK1HMvgo6xiTLG5rD5rZLDS+rp2Bjs=
 golang.org/x/net v0.10.0/go.mod h1:0qNGK6F8kojg2nk9dLZ2mShWaEBan6FAoqfSigmmuDg=
 golang.org/x/net v0.21.0/go.mod h1:bIjVDfnllIU7BJ2DNgfnXvpSvtn8VRwhlsaeUTyUS44=
-golang.org/x/net v0.27.0 h1:5K3Njcw06/l2y9vpGCSdcxWOYHOUk3dVNGDXN+FvAys=
-golang.org/x/net v0.27.0/go.mod h1:dDi0PyhWNoiUOrAS8uXv/vnScO4wnHQO4mj9fn/RytE=
+golang.org/x/net v0.30.0 h1:AcW1SDZMkb8IpzCdQUaIq2sP4sZ4zw+55h6ynffypl4=
+golang.org/x/net v0.30.0/go.mod h1:2wGyMJ5iFasEhkwi13ChkO/t1ECNC4X4eBKkVFyYFlU=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.1.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sync v0.7.0 h1:YsImfSBoP9QPYL0xyKJPq0gcaJdG3rInoqxTWbfQu9M=
-golang.org/x/sync v0.7.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
+golang.org/x/sync v0.8.0 h1:3NFvSEYkUoMifnESzZl15y791HH1qU2xm6eCJU5ZPXQ=
+golang.org/x/sync v0.8.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
-golang.org/x/sys v0.0.0-20190606203320-7fc4e5ec1444/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20191204072324-ce4227a45e2e/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20200217220822-9197077df867/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.2.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.5.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.8.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.10.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.17.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/sys v0.20.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
-golang.org/x/sys v0.22.0 h1:RI27ohtqKCnwULzJLqkv897zojh5/DwS/ENaMzUOaWI=
-golang.org/x/sys v0.22.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/sys v0.26.0 h1:KHjCJyddX0LoSTb3J+vWpupP9p0oznkqVk/IfjymZbo=
+golang.org/x/sys v0.26.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
 golang.org/x/term v0.5.0/go.mod h1:jMB1sMXY+tzblOD4FWmEbocvup2/aLOaQEp7JmGp78k=
@@ -129,8 +130,8 @@ golang.org/x/text v0.7.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
 golang.org/x/text v0.9.0/go.mod h1:e1OnstbJyHTd6l/uOt8jFFHp6TRDWZR/bV3emEE/zU8=
 golang.org/x/text v0.14.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=
 golang.org/x/text v0.15.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=
-golang.org/x/text v0.16.0 h1:a94ExnEXNtEwYLGJSIUxnWoxoRz/ZcCsV63ROupILh4=
-golang.org/x/text v0.16.0/go.mod h1:GhwF1Be+LQoKShO3cGOHzqOgRrGaYc9AvblQOmPVHnI=
+golang.org/x/text v0.19.0 h1:kTxAhCbGbxhK0IwgSKiMO5awPoDQ0RpfiVYBfK860YM=
+golang.org/x/text v0.19.0/go.mod h1:BuEKDfySbSR4drPmRPG/7iBdf8hvFMuRexcpahXilzY=
 golang.org/x/time v0.5.0 h1:o7cqy6amK/52YcAKIPlM3a+Fpj35zvRj2TP+e1xFSfk=
 golang.org/x/time v0.5.0/go.mod h1:3BpzKBy/shNhVucY/MWOyx10tF3SFh9QdLuxbVysPQM=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
@@ -154,5 +155,3 @@ gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gvisor.dev/gvisor v0.0.0-20230927004350-cbd86285d259 h1:TbRPT0HtzFP3Cno1zZo7yPzEEnfu8EjLfl6IU9VfqkQ=
 gvisor.dev/gvisor v0.0.0-20230927004350-cbd86285d259/go.mod h1:AVgIgHMwK63XvmAzWG9vLQ41YnVHN0du0tEC46fI7yY=
-nhooyr.io/websocket v1.8.11 h1:f/qXNc2/3DpoSZkHt1DQu6rj4zGC8JmkkLkWss0MgN0=
-nhooyr.io/websocket v1.8.11/go.mod h1:rN9OFWIUwuxg4fR5tELlYC04bXYowCP9GX47ivo2l+c=

src/admin/admin.go

@@ -238,27 +238,27 @@ func (a *AdminSocket) listen() {
 	if err == nil {
 		switch strings.ToLower(u.Scheme) {
 		case "unix":
-			if _, err := os.Stat(listenaddr[7:]); err == nil {
-				a.log.Debugln("Admin socket", listenaddr[7:], "already exists, trying to clean up")
-				if _, err := net.DialTimeout("unix", listenaddr[7:], time.Second*2); err == nil || err.(net.Error).Timeout() {
-					a.log.Errorln("Admin socket", listenaddr[7:], "already exists and is in use by another process")
+			if _, err := os.Stat(u.Path); err == nil {
+				a.log.Debugln("Admin socket", u.Path, "already exists, trying to clean up")
+				if _, err := net.DialTimeout("unix", u.Path, time.Second*2); err == nil || err.(net.Error).Timeout() {
+					a.log.Errorln("Admin socket", u.Path, "already exists and is in use by another process")
 					os.Exit(1)
 				} else {
-					if err := os.Remove(listenaddr[7:]); err == nil {
-						a.log.Debugln(listenaddr[7:], "was cleaned up")
+					if err := os.Remove(u.Path); err == nil {
+						a.log.Debugln(u.Path, "was cleaned up")
 					} else {
-						a.log.Errorln(listenaddr[7:], "already exists and was not cleaned up:", err)
+						a.log.Errorln(u.Path, "already exists and was not cleaned up:", err)
 						os.Exit(1)
 					}
 				}
 			}
-			a.listener, err = net.Listen("unix", listenaddr[7:])
+			a.listener, err = net.Listen("unix", u.Path)
 			if err == nil {
-				switch listenaddr[7:8] {
+				switch u.Path[:1] {
 				case "@": // maybe abstract namespace
 				default:
-					if err := os.Chmod(listenaddr[7:], 0660); err != nil {
-						a.log.Warnln("WARNING:", listenaddr[:7], "may have unsafe permissions!")
+					if err := os.Chmod(u.Path, 0660); err != nil {
+						a.log.Warnln("WARNING:", u.Path, "may have unsafe permissions!")
 					}
 				}
 			}

src/admin/getpaths.go

@@ -3,7 +3,7 @@ package admin
 import (
 	"encoding/hex"
 	"net"
-	"sort"
+	"slices"
 	"strings"
 
 	"github.com/yggdrasil-network/yggdrasil-go/src/address"
@@ -35,8 +35,8 @@ func (a *AdminSocket) getPathsHandler(_ *GetPathsRequest, res *GetPathsResponse)
 			Sequence:  p.Sequence,
 		})
 	}
-	sort.SliceStable(res.Paths, func(i, j int) bool {
-		return strings.Compare(res.Paths[i].PublicKey, res.Paths[j].PublicKey) < 0
+	slices.SortStableFunc(res.Paths, func(a, b PathEntry) int {
+		return strings.Compare(a.PublicKey, b.PublicKey)
 	})
 	return nil
 }

src/admin/getpeers.go

@@ -3,7 +3,8 @@ package admin
 import (
 	"encoding/hex"
 	"net"
-	"sort"
+	"slices"
+	"strings"
 	"time"
 
 	"github.com/yggdrasil-network/yggdrasil-go/src/address"
@@ -24,6 +25,7 @@ type PeerEntry struct {
 	PublicKey     string        `json:"key"`
 	Port          uint64        `json:"port"`
 	Priority      uint64        `json:"priority"`
+	Cost          uint64        `json:"cost"`
 	RXBytes       DataUnit      `json:"bytes_recvd,omitempty"`
 	TXBytes       DataUnit      `json:"bytes_sent,omitempty"`
 	Uptime        float64       `json:"uptime,omitempty"`
@@ -41,6 +43,7 @@ func (a *AdminSocket) getPeersHandler(_ *GetPeersRequest, res *GetPeersResponse)
 			Up:       p.Up,
 			Inbound:  p.Inbound,
 			Priority: uint64(p.Priority), // can't be uint8 thanks to gobind
+			Cost:     p.Cost,
 			URI:      p.URI,
 			RXBytes:  DataUnit(p.RXBytes),
 			TXBytes:  DataUnit(p.TXBytes),
@@ -59,17 +62,26 @@ func (a *AdminSocket) getPeersHandler(_ *GetPeersRequest, res *GetPeersResponse)
 		}
 		res.Peers = append(res.Peers, peer)
 	}
-	sort.Slice(res.Peers, func(i, j int) bool {
-		if res.Peers[i].Inbound == res.Peers[j].Inbound {
-			if res.Peers[i].PublicKey == res.Peers[j].PublicKey {
-				if res.Peers[i].Priority == res.Peers[j].Priority {
-					return res.Peers[i].Uptime > res.Peers[j].Uptime
-				}
-				return res.Peers[i].Priority < res.Peers[j].Priority
-			}
-			return res.Peers[i].PublicKey < res.Peers[j].PublicKey
+	slices.SortStableFunc(res.Peers, func(a, b PeerEntry) int {
+		if !a.Inbound && b.Inbound {
+			return -1
 		}
-		return !res.Peers[i].Inbound && res.Peers[j].Inbound
+		if a.Inbound && !b.Inbound {
+			return 1
+		}
+		if d := strings.Compare(a.PublicKey, b.PublicKey); d != 0 {
+			return d
+		}
+		if d := a.Priority - b.Priority; d != 0 {
+			return int(d)
+		}
+		if d := a.Cost - b.Cost; d != 0 {
+			return int(d)
+		}
+		if d := a.Uptime - b.Uptime; d != 0 {
+			return int(d)
+		}
+		return 0
 	})
 	return nil
 }

src/admin/getsessions.go

@@ -3,7 +3,7 @@ package admin
 import (
 	"encoding/hex"
 	"net"
-	"sort"
+	"slices"
 	"strings"
 
 	"github.com/yggdrasil-network/yggdrasil-go/src/address"
@@ -36,8 +36,8 @@ func (a *AdminSocket) getSessionsHandler(_ *GetSessionsRequest, res *GetSessions
 			Uptime:    s.Uptime.Seconds(),
 		})
 	}
-	sort.SliceStable(res.Sessions, func(i, j int) bool {
-		return strings.Compare(res.Sessions[i].PublicKey, res.Sessions[j].PublicKey) < 0
+	slices.SortStableFunc(res.Sessions, func(a, b SessionEntry) int {
+		return strings.Compare(a.PublicKey, b.PublicKey)
 	})
 	return nil
 }

src/admin/gettree.go

@@ -3,7 +3,7 @@ package admin
 import (
 	"encoding/hex"
 	"net"
-	"sort"
+	"slices"
 	"strings"
 
 	"github.com/yggdrasil-network/yggdrasil-go/src/address"
@@ -34,8 +34,8 @@ func (a *AdminSocket) getTreeHandler(_ *GetTreeRequest, res *GetTreeResponse) er
 			Sequence:  d.Sequence,
 		})
 	}
-	sort.SliceStable(res.Tree, func(i, j int) bool {
-		return strings.Compare(res.Tree[i].PublicKey, res.Tree[j].PublicKey) < 0
+	slices.SortStableFunc(res.Tree, func(a, b TreeEntry) int {
+		return strings.Compare(a.PublicKey, b.PublicKey)
 	})
 	return nil
 }

src/core/api.go

@@ -30,6 +30,7 @@ type PeerInfo struct {
 	Coords        []uint64
 	Port          uint64
 	Priority      uint8
+	Cost          uint64
 	RXBytes       uint64
 	TXBytes       uint64
 	Uptime        time.Duration
@@ -94,6 +95,7 @@ func (c *Core) GetPeers() []PeerInfo {
 				peerinfo.Port = p.Port
 				peerinfo.Priority = p.Priority
 				peerinfo.Latency = p.Latency
+				peerinfo.Cost = p.Cost
 			}
 			peers = append(peers, peerinfo)
 		}
@@ -148,7 +150,14 @@ func (c *Core) GetSessions() []SessionInfo {
 // parsed from a string of the form e.g. "tcp://a.b.c.d:e". In the case of a
 // link-local address, the interface should be provided as the second argument.
 func (c *Core) Listen(u *url.URL, sintf string) (*Listener, error) {
-	return c.links.listen(u, sintf)
+	return c.links.listen(u, sintf, false)
+}
+
+// ListenLocal starts a listener, like the Listen function, but is used for
+// more trustworthy situations where you want to ignore AllowedPublicKeys, i.e.
+// with multicast listeners.
+func (c *Core) ListenLocal(u *url.URL, sintf string) (*Listener, error) {
+	return c.links.listen(u, sintf, true)
 }
 
 // Address gets the IPv6 address of the Yggdrasil node. This is always a /128

src/core/core.go

@@ -127,7 +127,7 @@ func New(cert *tls.Certificate, logger Logger, opts ...SetupOption) (*Core, erro
 			c.log.Errorf("Invalid listener URI %q specified, ignoring\n", listenaddr)
 			continue
 		}
-		if _, err = c.links.listen(u, ""); err != nil {
+		if _, err = c.links.listen(u, "", false); err != nil {
 			c.log.Errorf("Failed to start listener %q: %s\n", listenaddr, err)
 		}
 	}

src/core/core_test.go

@@ -25,6 +25,27 @@ func GetLoggerWithPrefix(prefix string, verbose bool) *log.Logger {
 	return l
 }
 
+func require_NoError(t *testing.T, err error) {
+	t.Helper()
+	if err != nil {
+		t.Fatal(err)
+	}
+}
+
+func require_Equal[T comparable](t *testing.T, a, b T) {
+	t.Helper()
+	if a != b {
+		t.Fatalf("%v != %v", a, b)
+	}
+}
+
+func require_True(t *testing.T, a bool) {
+	t.Helper()
+	if !a {
+		t.Fatal("expected true")
+	}
+}
+
 // CreateAndConnectTwo creates two nodes. nodeB connects to nodeA.
 // Verbosity flag is passed to logger.
 func CreateAndConnectTwo(t testing.TB, verbose bool) (nodeA *Core, nodeB *Core) {
@@ -201,3 +222,69 @@ func BenchmarkCore_Start_Transfer(b *testing.B) {
 	}
 	<-done
 }
+
+func TestAllowedPublicKeys(t *testing.T) {
+	logger := GetLoggerWithPrefix("", false)
+	cfgA, cfgB := config.GenerateConfig(), config.GenerateConfig()
+	require_NoError(t, cfgA.GenerateSelfSignedCertificate())
+	require_NoError(t, cfgB.GenerateSelfSignedCertificate())
+
+	nodeA, err := New(cfgA.Certificate, logger, AllowedPublicKey("abcdef"))
+	require_NoError(t, err)
+	defer nodeA.Stop()
+
+	nodeB, err := New(cfgB.Certificate, logger)
+	require_NoError(t, err)
+	defer nodeB.Stop()
+
+	u, err := url.Parse("tcp://localhost:0")
+	require_NoError(t, err)
+
+	l, err := nodeA.Listen(u, "")
+	require_NoError(t, err)
+
+	u, err = url.Parse("tcp://" + l.Addr().String())
+	require_NoError(t, err)
+
+	require_NoError(t, nodeB.AddPeer(u, ""))
+
+	time.Sleep(time.Second)
+
+	peers := nodeB.GetPeers()
+	require_Equal(t, len(peers), 1)
+	require_True(t, !peers[0].Up)
+	require_True(t, peers[0].LastError != nil)
+}
+
+func TestAllowedPublicKeysLocal(t *testing.T) {
+	logger := GetLoggerWithPrefix("", false)
+	cfgA, cfgB := config.GenerateConfig(), config.GenerateConfig()
+	require_NoError(t, cfgA.GenerateSelfSignedCertificate())
+	require_NoError(t, cfgB.GenerateSelfSignedCertificate())
+
+	nodeA, err := New(cfgA.Certificate, logger, AllowedPublicKey("abcdef"))
+	require_NoError(t, err)
+	defer nodeA.Stop()
+
+	nodeB, err := New(cfgB.Certificate, logger)
+	require_NoError(t, err)
+	defer nodeB.Stop()
+
+	u, err := url.Parse("tcp://localhost:0")
+	require_NoError(t, err)
+
+	l, err := nodeA.ListenLocal(u, "")
+	require_NoError(t, err)
+
+	u, err = url.Parse("tcp://" + l.Addr().String())
+	require_NoError(t, err)
+
+	require_NoError(t, nodeB.AddPeer(u, ""))
+
+	time.Sleep(time.Second)
+
+	peers := nodeB.GetPeers()
+	require_Equal(t, len(peers), 1)
+	require_True(t, peers[0].Up)
+	require_True(t, peers[0].LastError == nil)
+}

src/core/link.go

@@ -108,7 +108,9 @@ func (l *links) shutdown() {
 			_ = listener.listener.Close()
 		}
 		for _, link := range l._links {
-			_ = link._conn.Close()
+			if link._conn != nil {
+				_ = link._conn.Close()
+			}
 		}
 	})
 }
@@ -334,7 +336,7 @@ func (l *links) add(u *url.URL, sintf string, linkType linkType) error {
 
 				// Give the connection to the handler. The handler will block
 				// for the lifetime of the connection.
-				if err = l.handler(linkType, options, lc, resetBackoff); err != nil && err != io.EOF {
+				if err = l.handler(linkType, options, lc, resetBackoff, false); err != nil && err != io.EOF {
 					l.core.log.Debugf("Link %s error: %s\n", info.uri, err)
 				}
 
@@ -357,8 +359,9 @@ func (l *links) add(u *url.URL, sintf string, linkType linkType) error {
 					if backoffNow() {
 						continue
 					}
-					return
 				}
+				// Ephemeral or incoming connections don't reconnect.
+				return
 			}
 		}()
 	})
@@ -392,7 +395,7 @@ func (l *links) remove(u *url.URL, sintf string, _ linkType) error {
 	return retErr
 }
 
-func (l *links) listen(u *url.URL, sintf string) (*Listener, error) {
+func (l *links) listen(u *url.URL, sintf string, local bool) (*Listener, error) {
 	ctx, cancel := context.WithCancel(l.core.ctx)
 	var protocol linkProtocol
 	switch strings.ToLower(u.Scheme) {
@@ -420,7 +423,10 @@ func (l *links) listen(u *url.URL, sintf string) (*Listener, error) {
 	li := &Listener{
 		listener: listener,
 		ctx:      ctx,
-		Cancel:   cancel,
+		Cancel: func() {
+			cancel()
+			_ = listener.Close()
+		},
 	}
 
 	var options linkOptions
@@ -516,7 +522,7 @@ func (l *links) listen(u *url.URL, sintf string) (*Listener, error) {
 
 				// Give the connection to the handler. The handler will block
 				// for the lifetime of the connection.
-				switch err = l.handler(linkTypeIncoming, options, lc, nil); {
+				switch err = l.handler(linkTypeIncoming, options, lc, nil, local); {
 				case err == nil:
 				case errors.Is(err, io.EOF):
 				case errors.Is(err, net.ErrClosed):
@@ -557,7 +563,7 @@ func (l *links) connect(ctx context.Context, u *url.URL, info linkInfo, options
 	return dialer.dial(ctx, u, info, options)
 }
 
-func (l *links) handler(linkType linkType, options linkOptions, conn net.Conn, success func()) error {
+func (l *links) handler(linkType linkType, options linkOptions, conn net.Conn, success func(), local bool) error {
 	meta := version_getBaseMetadata()
 	meta.publicKey = l.core.public
 	meta.priority = options.priority
@@ -600,19 +606,21 @@ func (l *links) handler(linkType linkType, options linkOptions, conn net.Conn, s
 		}
 	}
 	// Check if we're authorized to connect to this key / IP
-	var allowed map[[32]byte]struct{}
-	phony.Block(l.core, func() {
-		allowed = l.core.config._allowedPublicKeys
-	})
-	isallowed := len(allowed) == 0
-	for k := range allowed {
-		if bytes.Equal(k[:], meta.publicKey) {
-			isallowed = true
-			break
+	if !local {
+		var allowed map[[32]byte]struct{}
+		phony.Block(l.core, func() {
+			allowed = l.core.config._allowedPublicKeys
+		})
+		isallowed := len(allowed) == 0
+		for k := range allowed {
+			if bytes.Equal(k[:], meta.publicKey) {
+				isallowed = true
+				break
+			}
+		}
+		if linkType == linkTypeIncoming && !isallowed {
+			return fmt.Errorf("node public key %q is not in AllowedPublicKeys", hex.EncodeToString(meta.publicKey))
 		}
-	}
-	if linkType == linkTypeIncoming && !isallowed {
-		return fmt.Errorf("node public key %q is not in AllowedPublicKeys", hex.EncodeToString(meta.publicKey))
 	}
 
 	dir := "outbound"

src/core/link_ws.go

@@ -8,7 +8,7 @@ import (
 	"time"
 
 	"github.com/Arceliar/phony"
-	"nhooyr.io/websocket"
+	"github.com/coder/websocket"
 )
 
 type linkWS struct {

src/core/link_wss.go

@@ -7,7 +7,7 @@ import (
 	"net/url"
 
 	"github.com/Arceliar/phony"
-	"nhooyr.io/websocket"
+	"github.com/coder/websocket"
 )
 
 type linkWSS struct {

src/multicast/multicast.go

@@ -14,6 +14,7 @@ import (
 
 	"github.com/Arceliar/phony"
 	"github.com/gologme/log"
+	"github.com/wlynxg/anet"
 
 	"github.com/yggdrasil-network/yggdrasil-go/src/core"
 	"golang.org/x/crypto/blake2b"
@@ -148,7 +149,8 @@ func (m *Multicast) _stop() error {
 func (m *Multicast) _updateInterfaces() {
 	interfaces := m._getAllowedInterfaces()
 	for name, info := range interfaces {
-		addrs, err := info.iface.Addrs()
+		// 'anet' package is used here to avoid https://github.com/golang/go/issues/40569
+		addrs, err := anet.InterfaceAddrsByInterface(&info.iface)
 		if err != nil {
 			m.log.Warnf("Failed up get addresses for interface %s: %s", name, err)
 			delete(interfaces, name)
@@ -156,6 +158,7 @@ func (m *Multicast) _updateInterfaces() {
 		}
 		info.addrs = addrs
 		interfaces[name] = info
+		m.log.Debugf("Discovered addresses for interface %s: %s", name, addrs)
 	}
 	m._interfaces = interfaces
 }
@@ -174,10 +177,11 @@ func (m *Multicast) Interfaces() map[string]net.Interface {
 func (m *Multicast) _getAllowedInterfaces() map[string]*interfaceInfo {
 	interfaces := make(map[string]*interfaceInfo)
 	// Ask the system for network interfaces
-	allifaces, err := net.Interfaces()
+	// 'anet' package is used here to avoid https://github.com/golang/go/issues/40569
+	allifaces, err := anet.Interfaces()
 	if err != nil {
 		// Don't panic, since this may be from e.g. too many open files (from too much connection spam)
-		// TODO? log something
+		m.log.Debugf("Failed to get interfaces: %s", err)
 		return nil
 	}
 	// Work out which interfaces to announce on
@@ -186,6 +190,8 @@ func (m *Multicast) _getAllowedInterfaces() map[string]*interfaceInfo {
 		switch {
 		case iface.Flags&net.FlagUp == 0:
 			continue // Ignore interfaces that are down
+		case iface.Flags&net.FlagRunning == 0:
+			continue // Ignore interfaces that are not running
 		case iface.Flags&net.FlagMulticast == 0:
 			continue // Ignore non-multicast interfaces
 		case iface.Flags&net.FlagPointToPoint != 0:
@@ -321,7 +327,7 @@ func (m *Multicast) _announce() {
 					Host:     net.JoinHostPort(addrIP.String(), fmt.Sprintf("%d", info.port)),
 					RawQuery: v.Encode(),
 				}
-				if li, err := m.core.Listen(u, iface.Name); err == nil {
+				if li, err := m.core.ListenLocal(u, iface.Name); err == nil {
 					m.log.Debugln("Started multicasting on", iface.Name)
 					// Store the listener so that we can stop it later if needed
 					linfo = &listenerInfo{listener: li, time: time.Now(), port: info.port}

src/tun/iface.go

@@ -1,5 +1,11 @@
 package tun
 
+import (
+	"errors"
+
+	wgtun "golang.zx2c4.com/wireguard/tun"
+)
+
 const TUN_OFFSET_BYTES = 80 // sizeof(virtio_net_hdr)
 
 func (tun *TunAdapter) read() {
@@ -12,6 +18,10 @@ func (tun *TunAdapter) read() {
 	for {
 		n, err := tun.iface.Read(bufs, sizes, TUN_OFFSET_BYTES)
 		if err != nil {
+			if errors.Is(err, wgtun.ErrTooManySegments) {
+				tun.log.Debugln("TUN segments dropped: %v", err)
+				continue
+			}
 			tun.log.Errorln("Error reading TUN:", err)
 			return
 		}

src/tun/tun_freebsd.go

@@ -1,5 +1,5 @@
-//go:build openbsd || freebsd
-// +build openbsd freebsd
+//go:build freebsd
+// +build freebsd
 
 package tun
 
@@ -54,11 +54,6 @@ struct  in6_ifreq {
  290 };
 */
 
-type in6_ifreq_mtu struct {
-	ifr_name [syscall.IFNAMSIZ]byte
-	ifru_mtu int
-}
-
 type in6_ifreq_addr struct {
 	ifr_name  [syscall.IFNAMSIZ]byte
 	ifru_addr sockaddr_in6
@@ -112,26 +107,6 @@ func (tun *TunAdapter) setupAddress(addr string) error {
 	tun.log.Infof("Interface IPv6: %s", addr)
 	tun.log.Infof("Interface MTU: %d", tun.mtu)
 
-	// Create the MTU request
-	var ir in6_ifreq_mtu
-	copy(ir.ifr_name[:], tun.Name())
-	ir.ifru_mtu = int(tun.mtu)
-
-	// Set the MTU
-	if _, _, errno := unix.Syscall(unix.SYS_IOCTL, uintptr(sfd), uintptr(syscall.SIOCSIFMTU), uintptr(unsafe.Pointer(&ir))); errno != 0 {
-		err = errno
-		tun.log.Errorf("Error in SIOCSIFMTU: %v", errno)
-
-		// Fall back to ifconfig to set the MTU
-		cmd := exec.Command("ifconfig", tun.Name(), "mtu", string(tun.mtu))
-		tun.log.Warnf("Using ifconfig as fallback: %v", strings.Join(cmd.Args, " "))
-		output, err := cmd.CombinedOutput()
-		if err != nil {
-			tun.log.Errorf("SIOCSIFMTU fallback failed: %v.", err)
-			tun.log.Traceln(string(output))
-		}
-	}
-
 	// Create the address request
 	// FIXME: I don't work!
 	var ar in6_ifreq_addr

src/tun/tun_openbsd.go

@@ -0,0 +1,122 @@
+//go:build openbsd
+// +build openbsd
+
+package tun
+
+import (
+	"fmt"
+	"net"
+	"syscall"
+	"unsafe"
+
+	"golang.org/x/sys/unix"
+
+	wgtun "golang.zx2c4.com/wireguard/tun"
+)
+
+const (
+	SIOCAIFADDR_IN6       = 0x8080691a
+	ND6_INFINITE_LIFETIME = 0xffffffff
+)
+
+type in6_addrlifetime struct {
+	ia6t_expire    int64
+	ia6t_preferred int64
+	ia6t_vltime    uint32
+	ia6t_pltime    uint32
+}
+
+// Match types from the net package, effectively being [16]byte for IPv6 addresses.
+type in6_addr [16]uint8
+
+type sockaddr_in6 struct {
+	sin6_len      uint8
+	sin6_family   uint8
+	sin6_port     uint16
+	sin6_flowinfo uint32
+	sin6_addr     in6_addr
+	sin6_scope_id uint32
+}
+
+func (sa6 *sockaddr_in6) setSockaddr(addr [/*16*/]byte /* net.IP or net.IPMask */) {
+	sa6.sin6_len    = uint8(unsafe.Sizeof(*sa6))
+	sa6.sin6_family = unix.AF_INET6
+
+	for i := range sa6.sin6_addr {
+		sa6.sin6_addr[i] = addr[i]
+	}
+}
+
+type in6_aliasreq struct {
+	ifra_name       [syscall.IFNAMSIZ]byte
+	ifra_addr       sockaddr_in6
+	ifra_dstaddr    sockaddr_in6
+	ifra_prefixmask sockaddr_in6
+	ifra_flags      int32
+	ifra_lifetime   in6_addrlifetime
+}
+
+// Configures the TUN adapter with the correct IPv6 address and MTU.
+func (tun *TunAdapter) setup(ifname string, addr string, mtu uint64) error {
+	iface, err := wgtun.CreateTUN(ifname, int(mtu))
+	if err != nil {
+		return fmt.Errorf("failed to create TUN: %w", err)
+	}
+	tun.iface = iface
+	if mtu, err := iface.MTU(); err == nil {
+		tun.mtu = getSupportedMTU(uint64(mtu))
+	} else {
+		tun.mtu = 0
+	}
+	if addr != "" {
+		return tun.setupAddress(addr)
+	}
+	return nil
+}
+
+// Configures the "utun" adapter from an existing file descriptor.
+func (tun *TunAdapter) setupFD(fd int32, addr string, mtu uint64) error {
+	return fmt.Errorf("setup via FD not supported on this platform")
+}
+
+func (tun *TunAdapter) setupAddress(addr string) error {
+	var sfd int
+	var err error
+
+	ip, prefix, err := net.ParseCIDR(addr)
+	if err != nil {
+		tun.log.Errorf("Error in ParseCIDR: %v", err)
+		return err
+	}
+
+	// Create system socket
+	if sfd, err = unix.Socket(unix.AF_INET6, unix.SOCK_DGRAM, 0); err != nil {
+		tun.log.Printf("Create AF_INET6 socket failed: %v", err)
+		return err
+	}
+
+	// Friendly output
+	tun.log.Infof("Interface name: %s", tun.Name())
+	tun.log.Infof("Interface IPv6: %s", addr)
+	tun.log.Infof("Interface MTU: %d", tun.mtu)
+
+	// Create the address request
+	var ar in6_aliasreq
+	copy(ar.ifra_name[:], tun.Name())
+
+	ar.ifra_addr.setSockaddr(ip)
+
+	prefixmask := net.CIDRMask(prefix.Mask.Size())
+	ar.ifra_prefixmask.setSockaddr(prefixmask)
+
+	ar.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME
+	ar.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME
+
+	// Set the interface address
+	if err = unix.IoctlSetInt(sfd, SIOCAIFADDR_IN6, int(uintptr(unsafe.Pointer(&ar)))); err != nil {
+		tun.log.Errorf("Error in SIOCAIFADDR_IN6: %v", err)
+		return err
+	}
+
+	return nil
+}