Removed accidentially committed compiled file.

README.md

@@ -1,5 +1,9 @@
 # vppn: Virtual Potentially Private Network
 
+## TO DO
+
+* Double buffering in IFReader and ConnReader ?
+
 ## Hub Server Configuration
 
 ```
@@ -53,17 +57,15 @@ Sign-in and configure.
 
 Install the binary somewhere, for example `~/bin/vppn`.
 
-Add the API key for your network name in `~/.vppn/<netname>/apikey`.
-
 Create systemd file in `/etc/systemd/system/vppn.service`.
 
 ```
 [Service]
-AmbientCapabilities=AP_NET_ADMIN CAP_DAC_OVERRIDE CAP_CHOWN
+AmbientCapabilities=CAP_NET_BIND_SERVICE CAP_NET_ADMIN
 Type=simple
 User=user
 WorkingDirectory=/home/user/
-ExecStart=/home/user/bin/vppn -name my_net_name -hub https://my.hub
+ExecStart=/home/user/vppn run my_net_name https://my.hub my_api_key
 Restart=always
 RestartSec=8
 TimeoutStopSec=24

cmd/vppn/main.go

@@ -1,72 +1,11 @@
 package main
 
 import (
-	"flag"
 	"log"
-	"os"
-	"path/filepath"
-	"strings"
-
 	"vppn/peer"
-
-	"git.crumpington.com/lib/go/flock"
 )
 
 func main() {
 	log.SetFlags(0)
-
+	peer.Main2()
-	name := flag.String("name", "", "network name (required)")
-	hub := flag.String("hub", "", "hub base URL (required)")
-	flag.Parse()
-
-	if *name == "" || *hub == "" {
-		flag.Usage()
-		os.Exit(1)
-	}
-
-	apiKey, err := loadAPIKey(*name)
-	if err != nil {
-		log.Fatalf("api key: %v", err)
-	}
-
-	// Directory existence is guaranteed by the apikey file read above.
-	lockFile, err := flock.TryLock(vppnPath(*name, "lock"))
-	if err != nil {
-		log.Fatalf("lock: %v", err)
-	}
-	if lockFile == nil {
-		log.Fatalf("already running for network %q", *name)
-	}
-	defer flock.Unlock(lockFile)
-
-	state, err := peer.LoadOrInit(vppnPath(*name, "state.json"), *hub, apiKey)
-	if err != nil {
-		log.Fatalf("init: %v", err)
-	}
-
-	ifaceName := strings.TrimSuffix(state.LocalDomain, ".local")
-	app, err := peer.New(state, *hub, apiKey, ifaceName, state.LocalDomain, vppnPath(*name, "network.json"))
-	if err != nil {
-		log.Fatalf("start: %v", err)
-	}
-
-	if err := app.Run(); err != nil {
-		log.Fatalf("run: %v", err)
-	}
-}
-
-func loadAPIKey(name string) (string, error) {
-	data, err := os.ReadFile(vppnPath(name, "apikey"))
-	if err != nil {
-		return "", err
-	}
-	return strings.TrimSpace(string(data)), nil
-}
-
-func vppnPath(name, file string) string {
-	home, err := os.UserHomeDir()
-	if err != nil {
-		return filepath.Join(".vppn", name, file)
-	}
-	return filepath.Join(home, ".vppn", name, file)
 }

go.mod

@@ -3,21 +3,13 @@ module vppn
 go 1.25.1
 
 require (
-	git.crumpington.com/lib/go v0.10.0
+	git.crumpington.com/lib/go v0.9.1
-	golang.org/x/crypto v0.53.0
+	golang.org/x/crypto v0.42.0
-	golang.org/x/sys v0.46.0
+	golang.org/x/sys v0.36.0
-	golang.zx2c4.com/wireguard/wgctrl v0.0.0-20241231184526-a9ab2273dd10
 )
 
 require (
-	github.com/google/go-cmp v0.7.0 // indirect
+	github.com/mattn/go-sqlite3 v1.14.32 // indirect
-	github.com/josharian/native v1.1.0 // indirect
+	golang.org/x/net v0.44.0 // indirect
-	github.com/mattn/go-sqlite3 v1.14.45 // indirect
+	golang.org/x/text v0.29.0 // indirect
-	github.com/mdlayher/genetlink v1.4.0 // indirect
-	github.com/mdlayher/netlink v1.11.2 // indirect
-	github.com/mdlayher/socket v0.6.1 // indirect
-	golang.org/x/net v0.56.0 // indirect
-	golang.org/x/sync v0.21.0 // indirect
-	golang.org/x/text v0.38.0 // indirect
-	golang.zx2c4.com/wireguard v0.0.0-20260522210424-ecfc5a8d5446 // indirect
 )

go.sum

@@ -1,56 +1,12 @@
 git.crumpington.com/lib/go v0.9.1 h1:xLBzcgiZRB6Ky3Ce9hKE+Ko0YbkA4USF4eJk5i5RJF4=
 git.crumpington.com/lib/go v0.9.1/go.mod h1:5nnfjdnUnj/FHhakaliKQKsKeSkUb0GEUKF3PqRgUXg=
-git.crumpington.com/lib/go v0.9.2 h1:DZ7tzFM/S+zL5hexNo8zKbH7Ryi+VtvSMRzCMnlz+c4=
-git.crumpington.com/lib/go v0.9.2/go.mod h1:5nnfjdnUnj/FHhakaliKQKsKeSkUb0GEUKF3PqRgUXg=
-git.crumpington.com/lib/go v0.10.0 h1:4O+o9QBVcre8RYESAXhxJ1kT0w1tIakUdt/rV4v4riw=
-git.crumpington.com/lib/go v0.10.0/go.mod h1:8y838PnV7dM6QT0XwLMuG2ulDNtCv4NmdSJIEqGViKg=
-github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
-github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
-github.com/google/go-cmp v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
-github.com/google/go-cmp v0.7.0/go.mod h1:pXiqmnSA92OHEEa9HXL2W4E7lf9JzCmGVUdgjX3N/iU=
-github.com/josharian/native v1.1.0 h1:uuaP0hAbW7Y4l0ZRQ6C9zfb7Mg1mbFKry/xzDAfmtLA=
-github.com/josharian/native v1.1.0/go.mod h1:7X/raswPFr05uY3HiLlYeyQntB6OO7E/d2Cu7qoaN2w=
 github.com/mattn/go-sqlite3 v1.14.32 h1:JD12Ag3oLy1zQA+BNn74xRgaBbdhbNIDYvQUEuuErjs=
 github.com/mattn/go-sqlite3 v1.14.32/go.mod h1:Uh1q+B4BYcTPb+yiD3kU8Ct7aC0hY9fxUwlHK0RXw+Y=
-github.com/mattn/go-sqlite3 v1.14.45 h1:6KA/spDguL3KV8rnybG7ezSaE4SeMR3KC9VbUoAQaIk=
-github.com/mattn/go-sqlite3 v1.14.45/go.mod h1:pjEuOr8IwzLJP2MfGeTb0A35jauH+C2kbHKBr7yXKVQ=
-github.com/mdlayher/genetlink v1.3.2 h1:KdrNKe+CTu+IbZnm/GVUMXSqBBLqcGpRDa0xkQy56gw=
-github.com/mdlayher/genetlink v1.3.2/go.mod h1:tcC3pkCrPUGIKKsCsp0B3AdaaKuHtaxoJRz3cc+528o=
-github.com/mdlayher/genetlink v1.4.0 h1:f/Xs7Y2T+GyX9b3dbiUhnLE9InGs5F9RxJ2JwBMl71o=
-github.com/mdlayher/genetlink v1.4.0/go.mod h1:d1hrKr8fwZU2JkcAtQUAzeTrI7nbgQSl+5k1cC0biSA=
-github.com/mdlayher/netlink v1.7.2 h1:/UtM3ofJap7Vl4QWCPDGXY8d3GIY2UGSDbK+QWmY8/g=
-github.com/mdlayher/netlink v1.7.2/go.mod h1:xraEF7uJbxLhc5fpHL4cPe221LI2bdttWlU+ZGLfQSw=
-github.com/mdlayher/netlink v1.11.2 h1:HKh2jqe+omdSWcQ88nrT7INE61B0NXfiSPFdgL4YbNI=
-github.com/mdlayher/netlink v1.11.2/go.mod h1:uT2Yc/QLaZubzDpZIBi9d4GoeLwtp3x1AMeqSRrK2sA=
-github.com/mdlayher/socket v0.5.1 h1:VZaqt6RkGkt2OE9l3GcC6nZkqD3xKeQLyfleW/uBcos=
-github.com/mdlayher/socket v0.5.1/go.mod h1:TjPLHI1UgwEv5J1B5q0zTZq12A/6H7nKmtTanQE37IQ=
-github.com/mdlayher/socket v0.6.1 h1:M7uj2NtuujUY4mYr1C57NmfNiRHbkKpnBxO856lsc3A=
-github.com/mdlayher/socket v0.6.1/go.mod h1:+/SGtqc9V+5dAuRgQsU0fGBI+oRDiW7O2Obx10OIWfg=
-github.com/mikioh/ipaddr v0.0.0-20190404000644-d465c8ab6721 h1:RlZweED6sbSArvlE924+mUcZuXKLBHA35U7LN621Bws=
-github.com/mikioh/ipaddr v0.0.0-20190404000644-d465c8ab6721/go.mod h1:Ickgr2WtCLZ2MDGd4Gr0geeCH5HybhRJbonOgQpvSxc=
 golang.org/x/crypto v0.42.0 h1:chiH31gIWm57EkTXpwnqf8qeuMUi0yekh6mT2AvFlqI=
 golang.org/x/crypto v0.42.0/go.mod h1:4+rDnOTJhQCx2q7/j6rAN5XDw8kPjeaXEUR2eL94ix8=
-golang.org/x/crypto v0.53.0 h1:QZ4Muo8THX6CizN2vPPd5fBGHyogrdK9fG4wLPFUsto=
-golang.org/x/crypto v0.53.0/go.mod h1:DNLU434OwVakk9PzuwV8w62mAJpRJL3vsgcfp4Qnsio=
 golang.org/x/net v0.44.0 h1:evd8IRDyfNBMBTTY5XRF1vaZlD+EmWx6x8PkhR04H/I=
 golang.org/x/net v0.44.0/go.mod h1:ECOoLqd5U3Lhyeyo/QDCEVQ4sNgYsqvCZ722XogGieY=
-golang.org/x/net v0.56.0 h1:Rw8j/hFzGvJUZwNBXnAtf5sVDVt+65SK2C7IxCxZt5o=
-golang.org/x/net v0.56.0/go.mod h1:D3Ku6r+V6JROoZK144D2XfMHFcMq/0zSfLelVTCFKec=
-golang.org/x/sync v0.17.0 h1:l60nONMj9l5drqw6jlhIELNv9I0A4OFgRsG9k2oT9Ug=
-golang.org/x/sync v0.17.0/go.mod h1:9KTHXmSnoGruLpwFjVSX0lNNA75CykiMECbovNTZqGI=
-golang.org/x/sync v0.21.0 h1:HLII4xRRTtCRkxYp4HNFF0Js/Og6q2i++KXbg0gHCwM=
-golang.org/x/sync v0.21.0/go.mod h1:9xrNwdLfx4jkKbNva9FpL6vEN7evnE43NNNJQ2LF3+0=
 golang.org/x/sys v0.36.0 h1:KVRy2GtZBrk1cBYA7MKu5bEZFxQk4NIDV6RLVcC8o0k=
 golang.org/x/sys v0.36.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
-golang.org/x/sys v0.46.0 h1:noSf2Fq6F8DBgS+LysIkx7rIExoNHJsxOAtPp4rthXw=
-golang.org/x/sys v0.46.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
 golang.org/x/text v0.29.0 h1:1neNs90w9YzJ9BocxfsQNHKuAT4pkghyXc4nhZ6sJvk=
 golang.org/x/text v0.29.0/go.mod h1:7MhJOA9CD2qZyOKYazxdYMF85OwPdEr9jTtBpO7ydH4=
-golang.org/x/text v0.38.0 h1:sXmwo9DwP3OK9EZ7PqAdaooSGozfl/3a6/xJcbzPRhE=
-golang.org/x/text v0.38.0/go.mod h1:YXZt3QhHUKYT53r2lLKFIVi6Ao1jdzrTR/KQ09qyxF4=
-golang.zx2c4.com/wireguard v0.0.0-20231211153847-12269c276173 h1:/jFs0duh4rdb8uIfPMv78iAJGcPKDeqAFnaLBropIC4=
-golang.zx2c4.com/wireguard v0.0.0-20231211153847-12269c276173/go.mod h1:tkCQ4FQXmpAgYVh++1cq16/dH4QJtmvpRv19DWGAHSA=
-golang.zx2c4.com/wireguard v0.0.0-20260522210424-ecfc5a8d5446 h1:cqHQ3AycTHvM2R7ikgyX57D+XvtcSnGylsLkOVhta/w=
-golang.zx2c4.com/wireguard v0.0.0-20260522210424-ecfc5a8d5446/go.mod h1:rpwXGsirqLqN2L0JDJQlwOboGHmptD5ZD6T2VmcqhTw=
-golang.zx2c4.com/wireguard/wgctrl v0.0.0-20241231184526-a9ab2273dd10 h1:3GDAcqdIg1ozBNLgPy4SLT84nfcBjr6rhGtXYtrkWLU=
-golang.zx2c4.com/wireguard/wgctrl v0.0.0-20241231184526-a9ab2273dd10/go.mod h1:T97yPqesLiNrOYxkwmhMI0ZIlJDm+p0PMR8eRVeR5tQ=

hub/api/api.go

@@ -19,10 +19,8 @@ import (
 var migrations embed.FS
 
 type API struct {
-	db         *sql.DB
+	db   *sql.DB
-	lock       sync.Mutex
+	lock sync.Mutex
-	sessionsMu sync.Mutex
-	sessions   map[string]*Session
 }
 
 func New(dbPath string) (*API, error) {
@@ -36,17 +34,10 @@ func New(dbPath string) (*API, error) {
 	}
 
 	a := &API{
-		db:       sqlDB,
+		db: sqlDB,
-		sessions: make(map[string]*Session),
 	}
 
-	if err := a.ensurePassword(); err != nil {
+	return a, a.ensurePassword()
-		return nil, err
-	}
-
-	go a.sweepSessions()
-
-	return a, nil
 }
 
 func (a *API) ensurePassword() error {
@@ -71,8 +62,12 @@ func (a *API) ensurePassword() error {
 	return db.Config_Insert(a.db, conf)
 }
 
-func (a *API) Config_Get() (*Config, error) {
+func (a *API) Config_Get() *Config {
-	return db.Config_Get(a.db, 1)
+	conf, err := db.Config_Get(a.db, 1)
+	if err != nil {
+		panic(err)
+	}
+	return conf
 }
 
 func (a *API) Config_Update(conf *Config) error {
@@ -80,78 +75,56 @@ func (a *API) Config_Update(conf *Config) error {
 }
 
 func (a *API) Session_Delete(sessionID string) error {
-	a.sessionsMu.Lock()
+	return db.Session_Delete(a.db, sessionID)
-	defer a.sessionsMu.Unlock()
-	delete(a.sessions, sessionID)
-	return nil
 }
 
-const (
+func (a *API) Session_Get(sessionID string) (*Session, error) {
-	sessionTTLSecs    = 86400 * 21 // sessions expire 21 days after last use
+	if sessionID == "" {
-	sessionSweepEvery = time.Hour  // cadence of expired-session eviction
+		return a.session_CreatePub()
-)
-
-// Session_Get returns a snapshot copy of the signed-in session for sessionID,
-// or the zero Session if the cookie is missing/unknown/expired. It never
-// creates a session, so anonymous requests cost no memory — a session is minted
-// only by Session_SignIn. Returning a value (not the stored pointer) keeps
-// callers from racing on the shared struct.
-func (a *API) Session_Get(sessionID string) (Session, error) {
-	a.sessionsMu.Lock()
-	defer a.sessionsMu.Unlock()
-
-	s, ok := a.sessions[sessionID]
-
-	if sessionID == "" || !ok {
-		return Session{}, nil
 	}
 
-	if timeSince(s.LastSeenAt) > sessionTTLSecs {
+	session, err := db.Session_Get(a.db, sessionID)
-		delete(a.sessions, sessionID)
-		return Session{}, nil
-	}
-
-	s.LastSeenAt = time.Now().Unix()
-	return *s, nil
-}
-
-// Session_SignIn verifies pwd and, on success, mints a fresh signed-in session,
-// returning it so the caller can set the cookie. A new ID per sign-in rotates
-// the session at the privilege boundary (session-fixation resistance).
-func (a *API) Session_SignIn(pwd string) (Session, error) {
-	conf, err := a.Config_Get()
 	if err != nil {
-		return Session{}, err
+		return a.session_CreatePub()
-	}
-	if err := bcrypt.CompareHashAndPassword(conf.Password, []byte(pwd)); err != nil {
-		return Session{}, ErrNotAuthorized
 	}
 
-	a.sessionsMu.Lock()
+	if timeSince(session.LastSeenAt) > 86400*21 {
-	defer a.sessionsMu.Unlock()
+		return a.session_CreatePub()
+	}
+
+	if timeSince(session.LastSeenAt) > 86400*7 {
+		session.LastSeenAt = time.Now().Unix()
+		if err := db.Session_UpdateLastSeenAt(a.db, session.SessionID); err != nil {
+			log.Printf("Failed to update session: %v", err)
+		}
+	}
+
+	return session, nil
+}
+
+func (a *API) session_CreatePub() (*Session, error) {
 	s := &Session{
 		SessionID:  idgen.NewToken(),
-		SignedIn:   true,
+		CSRF:       idgen.NewToken(),
+		SignedIn:   false,
 		CreatedAt:  time.Now().Unix(),
 		LastSeenAt: time.Now().Unix(),
 	}
-	a.sessions[s.SessionID] = s
+	err := db.Session_Insert(a.db, s)
-	return *s, nil
+	return s, err
 }
 
-// sweepSessions periodically evicts sessions past their TTL. Without it, a
+func (a *API) Session_DeleteBefore(timestamp int64) error {
-// signed-in session whose ID is never presented again would linger forever
+	return db.Session_DeleteBefore(a.db, timestamp)
-// (Session_Get only evicts on a lookup of that same ID).
+}
-func (a *API) sweepSessions() {
+
-	for range time.Tick(sessionSweepEvery) {
+func (a *API) Session_SignIn(s *Session, pwd string) error {
-		a.sessionsMu.Lock()
+	conf := a.Config_Get()
-		for id, s := range a.sessions {
+	if err := bcrypt.CompareHashAndPassword(conf.Password, []byte(pwd)); err != nil {
-			if timeSince(s.LastSeenAt) > sessionTTLSecs {
+		return ErrNotAuthorized
-				delete(a.sessions, id)
-			}
-		}
-		a.sessionsMu.Unlock()
 	}
+
+	return db.Session_SetSignedIn(a.db, s.SessionID)
 }
 
 func (a *API) Network_Create(n *Network) error {
@@ -168,13 +141,14 @@ func (a *API) Network_Get(id int64) (*Network, error) {
 }
 
 func (a *API) Network_List() ([]*Network, error) {
-	const query = db.Network_SelectQuery + ` ORDER BY LocalDomain ASC`
+	const query = db.Network_SelectQuery + ` ORDER BY Name ASC`
 	return db.Network_List(a.db, query)
 }
 
 func (a *API) Peer_CreateNew(p *Peer) error {
-	p.WGPubKey = []byte{}
+	p.Version = idgen.NextID(0)
-	p.SignPubKey = []byte{}
+	p.PubKey = []byte{}
+	p.PubSignKey = []byte{}
 	p.APIKey = idgen.NewToken()
 
 	return db.Peer_Insert(a.db, p)
@@ -184,22 +158,21 @@ func (a *API) Peer_Init(peer *Peer, args m.PeerInitArgs) error {
 	a.lock.Lock()
 	defer a.lock.Unlock()
 
-	// Re-read from DB inside the lock — the caller's copy was fetched before
+	peer.Version = idgen.NextID(0)
-	// we held the lock, so it may be stale under concurrent requests.
+	peer.PubKey = args.EncPubKey
-	current, err := db.Peer_Get(a.db, peer.NetworkID, peer.PeerIP)
+	peer.PubSignKey = args.PubSignKey
-	if err != nil {
-		return err
-	}
-	if len(current.WGPubKey) != 0 {
-		return errors.New("peer already initialized")
-	}
-
-	peer.WGPubKey = args.WGPubKey
-	peer.SignPubKey = args.SignPubKey
 
 	return db.Peer_UpdateFull(a.db, peer)
 }
 
+func (a *API) Peer_Update(p *Peer) error {
+	a.lock.Lock()
+	defer a.lock.Unlock()
+
+	p.Version = idgen.NextID(0)
+	return db.Peer_Update(a.db, p)
+}
+
 func (a *API) Peer_Delete(networkID int64, peerIP byte) error {
 	return db.Peer_Delete(a.db, networkID, peerIP)
 }

hub/api/db/generated.go

@@ -123,9 +123,7 @@ func Config_Get(
 ) {
 	row = &Config{}
 	r := tx.QueryRow("SELECT ConfigID,Password FROM config WHERE ConfigID=?", ConfigID)
-	if err = r.Scan(&row.ConfigID, &row.Password); err != nil {
+	err = r.Scan(&row.ConfigID, &row.Password)
-		row = nil
-	}
 	return
 }
 
@@ -139,9 +137,7 @@ func Config_GetWhere(
 ) {
 	row = &Config{}
 	r := tx.QueryRow(query, args...)
-	if err = r.Scan(&row.ConfigID, &row.Password); err != nil {
+	err = r.Scan(&row.ConfigID, &row.Password)
-		row = nil
-	}
 	return
 }
 
@@ -186,17 +182,135 @@ func Config_List(
 	return l, nil
 }
 
+// ----------------------------------------------------------------------------
+// Table: sessions
+// ----------------------------------------------------------------------------
+
+type Session struct {
+	SessionID  string
+	CSRF       string
+	SignedIn   bool
+	CreatedAt  int64
+	LastSeenAt int64
+}
+
+const Session_SelectQuery = "SELECT SessionID,CSRF,SignedIn,CreatedAt,LastSeenAt FROM sessions"
+
+func Session_Insert(
+	tx TX,
+	row *Session,
+) (err error) {
+	Session_Sanitize(row)
+	if err = Session_Validate(row); err != nil {
+		return err
+	}
+
+	_, err = tx.Exec("INSERT INTO sessions(SessionID,CSRF,SignedIn,CreatedAt,LastSeenAt) VALUES(?,?,?,?,?)", row.SessionID, row.CSRF, row.SignedIn, row.CreatedAt, row.LastSeenAt)
+	return err
+}
+
+func Session_Delete(
+	tx TX,
+	SessionID string,
+) (err error) {
+	result, err := tx.Exec("DELETE FROM sessions WHERE SessionID=?", SessionID)
+	if err != nil {
+		return err
+	}
+
+	n, err := result.RowsAffected()
+	if err != nil {
+		panic(err)
+	}
+	switch n {
+	case 0:
+		return sql.ErrNoRows
+	case 1:
+		return nil
+	default:
+		panic("multiple rows deleted")
+	}
+}
+
+func Session_Get(
+	tx TX,
+	SessionID string,
+) (
+	row *Session,
+	err error,
+) {
+	row = &Session{}
+	r := tx.QueryRow("SELECT SessionID,CSRF,SignedIn,CreatedAt,LastSeenAt FROM sessions WHERE SessionID=?", SessionID)
+	err = r.Scan(&row.SessionID, &row.CSRF, &row.SignedIn, &row.CreatedAt, &row.LastSeenAt)
+	return
+}
+
+func Session_GetWhere(
+	tx TX,
+	query string,
+	args ...any,
+) (
+	row *Session,
+	err error,
+) {
+	row = &Session{}
+	r := tx.QueryRow(query, args...)
+	err = r.Scan(&row.SessionID, &row.CSRF, &row.SignedIn, &row.CreatedAt, &row.LastSeenAt)
+	return
+}
+
+func Session_Iterate(
+	tx TX,
+	query string,
+	args ...any,
+) iter.Seq2[*Session, error] {
+	rows, err := tx.Query(query, args...)
+	if err != nil {
+		return func(yield func(*Session, error) bool) {
+			yield(nil, err)
+		}
+	}
+
+	return func(yield func(*Session, error) bool) {
+		defer rows.Close()
+		for rows.Next() {
+			row := &Session{}
+			err := rows.Scan(&row.SessionID, &row.CSRF, &row.SignedIn, &row.CreatedAt, &row.LastSeenAt)
+			if !yield(row, err) {
+				return
+			}
+		}
+	}
+}
+
+func Session_List(
+	tx TX,
+	query string,
+	args ...any,
+) (
+	l []*Session,
+	err error,
+) {
+	for row, err := range Session_Iterate(tx, query, args...) {
+		if err != nil {
+			return nil, err
+		}
+		l = append(l, row)
+	}
+	return l, nil
+}
+
 // ----------------------------------------------------------------------------
 // Table: networks
 // ----------------------------------------------------------------------------
 
 type Network struct {
-	NetworkID   int64
+	NetworkID int64
-	LocalDomain string
+	Name      string
-	Network     []byte
+	Network   []byte
 }
 
-const Network_SelectQuery = "SELECT NetworkID,LocalDomain,Network FROM networks"
+const Network_SelectQuery = "SELECT NetworkID,Name,Network FROM networks"
 
 func Network_Insert(
 	tx TX,
@@ -207,7 +321,7 @@ func Network_Insert(
 		return err
 	}
 
-	_, err = tx.Exec("INSERT INTO networks(NetworkID,LocalDomain,Network) VALUES(?,?,?)", row.NetworkID, row.LocalDomain, row.Network)
+	_, err = tx.Exec("INSERT INTO networks(NetworkID,Name,Network) VALUES(?,?,?)", row.NetworkID, row.Name, row.Network)
 	return err
 }
 
@@ -220,7 +334,7 @@ func Network_UpdateFull(
 		return err
 	}
 
-	result, err := tx.Exec("UPDATE networks SET LocalDomain=?,Network=? WHERE NetworkID=?", row.LocalDomain, row.Network, row.NetworkID)
+	result, err := tx.Exec("UPDATE networks SET Name=?,Network=? WHERE NetworkID=?", row.Name, row.Network, row.NetworkID)
 	if err != nil {
 		return err
 	}
@@ -270,10 +384,8 @@ func Network_Get(
 	err error,
 ) {
 	row = &Network{}
-	r := tx.QueryRow("SELECT NetworkID,LocalDomain,Network FROM networks WHERE NetworkID=?", NetworkID)
+	r := tx.QueryRow("SELECT NetworkID,Name,Network FROM networks WHERE NetworkID=?", NetworkID)
-	if err = r.Scan(&row.NetworkID, &row.LocalDomain, &row.Network); err != nil {
+	err = r.Scan(&row.NetworkID, &row.Name, &row.Network)
-		row = nil
-	}
 	return
 }
 
@@ -287,9 +399,7 @@ func Network_GetWhere(
 ) {
 	row = &Network{}
 	r := tx.QueryRow(query, args...)
-	if err = r.Scan(&row.NetworkID, &row.LocalDomain, &row.Network); err != nil {
+	err = r.Scan(&row.NetworkID, &row.Name, &row.Network)
-		row = nil
-	}
 	return
 }
 
@@ -309,7 +419,7 @@ func Network_Iterate(
 		defer rows.Close()
 		for rows.Next() {
 			row := &Network{}
-			err := rows.Scan(&row.NetworkID, &row.LocalDomain, &row.Network)
+			err := rows.Scan(&row.NetworkID, &row.Name, &row.Network)
 			if !yield(row, err) {
 				return
 			}
@@ -341,17 +451,17 @@ func Network_List(
 type Peer struct {
 	NetworkID  int64
 	PeerIP     byte
+	Version    int64
 	APIKey     string
 	Name       string
-	Addr4      []byte
+	PublicIP   []byte
-	Addr6      []byte
 	Port       uint16
 	Relay      bool
-	WGPubKey   []byte
+	PubKey     []byte
-	SignPubKey []byte
+	PubSignKey []byte
 }
 
-const Peer_SelectQuery = "SELECT NetworkID,PeerIP,APIKey,Name,Addr4,Addr6,Port,Relay,WGPubKey,SignPubKey FROM peers"
+const Peer_SelectQuery = "SELECT NetworkID,PeerIP,Version,APIKey,Name,PublicIP,Port,Relay,PubKey,PubSignKey FROM peers"
 
 func Peer_Insert(
 	tx TX,
@@ -362,10 +472,38 @@ func Peer_Insert(
 		return err
 	}
 
-	_, err = tx.Exec("INSERT INTO peers(NetworkID,PeerIP,APIKey,Name,Addr4,Addr6,Port,Relay,WGPubKey,SignPubKey) VALUES(?,?,?,?,?,?,?,?,?,?)", row.NetworkID, row.PeerIP, row.APIKey, row.Name, row.Addr4, row.Addr6, row.Port, row.Relay, row.WGPubKey, row.SignPubKey)
+	_, err = tx.Exec("INSERT INTO peers(NetworkID,PeerIP,Version,APIKey,Name,PublicIP,Port,Relay,PubKey,PubSignKey) VALUES(?,?,?,?,?,?,?,?,?,?)", row.NetworkID, row.PeerIP, row.Version, row.APIKey, row.Name, row.PublicIP, row.Port, row.Relay, row.PubKey, row.PubSignKey)
 	return err
 }
 
+func Peer_Update(
+	tx TX,
+	row *Peer,
+) (err error) {
+	Peer_Sanitize(row)
+	if err = Peer_Validate(row); err != nil {
+		return err
+	}
+
+	result, err := tx.Exec("UPDATE peers SET Version=?,Name=?,PublicIP=?,Port=?,Relay=? WHERE NetworkID=? AND PeerIP=?", row.Version, row.Name, row.PublicIP, row.Port, row.Relay, row.NetworkID, row.PeerIP)
+	if err != nil {
+		return err
+	}
+
+	n, err := result.RowsAffected()
+	if err != nil {
+		panic(err)
+	}
+	switch n {
+	case 0:
+		return sql.ErrNoRows
+	case 1:
+		return nil
+	default:
+		panic("multiple rows updated")
+	}
+}
+
 func Peer_UpdateFull(
 	tx TX,
 	row *Peer,
@@ -375,7 +513,7 @@ func Peer_UpdateFull(
 		return err
 	}
 
-	result, err := tx.Exec("UPDATE peers SET APIKey=?,Name=?,Addr4=?,Addr6=?,Port=?,Relay=?,WGPubKey=?,SignPubKey=? WHERE NetworkID=? AND PeerIP=?", row.APIKey, row.Name, row.Addr4, row.Addr6, row.Port, row.Relay, row.WGPubKey, row.SignPubKey, row.NetworkID, row.PeerIP)
+	result, err := tx.Exec("UPDATE peers SET Version=?,APIKey=?,Name=?,PublicIP=?,Port=?,Relay=?,PubKey=?,PubSignKey=? WHERE NetworkID=? AND PeerIP=?", row.Version, row.APIKey, row.Name, row.PublicIP, row.Port, row.Relay, row.PubKey, row.PubSignKey, row.NetworkID, row.PeerIP)
 	if err != nil {
 		return err
 	}
@@ -427,10 +565,8 @@ func Peer_Get(
 	err error,
 ) {
 	row = &Peer{}
-	r := tx.QueryRow("SELECT NetworkID,PeerIP,APIKey,Name,Addr4,Addr6,Port,Relay,WGPubKey,SignPubKey FROM peers WHERE NetworkID=? AND PeerIP=?", NetworkID, PeerIP)
+	r := tx.QueryRow("SELECT NetworkID,PeerIP,Version,APIKey,Name,PublicIP,Port,Relay,PubKey,PubSignKey FROM peers WHERE NetworkID=? AND PeerIP=?", NetworkID, PeerIP)
-	if err = r.Scan(&row.NetworkID, &row.PeerIP, &row.APIKey, &row.Name, &row.Addr4, &row.Addr6, &row.Port, &row.Relay, &row.WGPubKey, &row.SignPubKey); err != nil {
+	err = r.Scan(&row.NetworkID, &row.PeerIP, &row.Version, &row.APIKey, &row.Name, &row.PublicIP, &row.Port, &row.Relay, &row.PubKey, &row.PubSignKey)
-		row = nil
-	}
 	return
 }
 
@@ -444,9 +580,7 @@ func Peer_GetWhere(
 ) {
 	row = &Peer{}
 	r := tx.QueryRow(query, args...)
-	if err = r.Scan(&row.NetworkID, &row.PeerIP, &row.APIKey, &row.Name, &row.Addr4, &row.Addr6, &row.Port, &row.Relay, &row.WGPubKey, &row.SignPubKey); err != nil {
+	err = r.Scan(&row.NetworkID, &row.PeerIP, &row.Version, &row.APIKey, &row.Name, &row.PublicIP, &row.Port, &row.Relay, &row.PubKey, &row.PubSignKey)
-		row = nil
-	}
 	return
 }
 
@@ -466,7 +600,7 @@ func Peer_Iterate(
 		defer rows.Close()
 		for rows.Next() {
 			row := &Peer{}
-			err := rows.Scan(&row.NetworkID, &row.PeerIP, &row.APIKey, &row.Name, &row.Addr4, &row.Addr6, &row.Port, &row.Relay, &row.WGPubKey, &row.SignPubKey)
+			err := rows.Scan(&row.NetworkID, &row.PeerIP, &row.Version, &row.APIKey, &row.Name, &row.PublicIP, &row.Port, &row.Relay, &row.PubKey, &row.PubSignKey)
 			if !yield(row, err) {
 				return
 			}

hub/api/db/sanitize-validate.go

@@ -8,11 +8,9 @@ import (
 
 var (
 	ErrInvalidIP       = errors.New("invalid IP")
-	ErrInvalidPeerIP   = errors.New("invalid peer IP")
 	ErrNonPrivateIP    = errors.New("non-private IP")
 	ErrInvalidPort     = errors.New("invalid port")
 	ErrInvalidNetName  = errors.New("invalid network name")
-	ErrNetNameNotLocal = errors.New("network name must end with .local")
 	ErrInvalidPeerName = errors.New("invalid peer name")
 )
 
@@ -23,8 +21,15 @@ func Config_Validate(c *Config) error {
 	return nil
 }
 
+func Session_Sanitize(s *Session) {
+}
+
+func Session_Validate(s *Session) error {
+	return nil
+}
+
 func Network_Sanitize(n *Network) {
-	n.LocalDomain = strings.TrimSpace(n.LocalDomain)
+	n.Name = strings.TrimSpace(n.Name)
 
 	if addr, ok := netip.AddrFromSlice(n.Network); ok {
 		n.Network = addr.AsSlice()
@@ -32,17 +37,12 @@ func Network_Sanitize(n *Network) {
 }
 
 func Network_Validate(c *Network) error {
-	// 15 bytes is linux limit for network interface names. With ending .local,
+	// 16 bytes is linux limit for network interface names.
-	// max length is 21.
+	if len(c.Name) == 0 || len(c.Name) > 16 {
-	if len(c.LocalDomain) == 0 || len(c.LocalDomain) > 21 {
 		return ErrInvalidNetName
 	}
 
-	if !strings.HasSuffix(c.LocalDomain, ".local") {
+	for _, c := range c.Name {
-		return ErrNetNameNotLocal
-	}
-
-	for _, c := range strings.TrimSuffix(c.LocalDomain, ".local") {
 		if c >= 'a' && c <= 'z' {
 			continue
 		}
@@ -66,35 +66,21 @@ func Network_Validate(c *Network) error {
 
 func Peer_Sanitize(p *Peer) {
 	p.Name = strings.TrimSpace(p.Name)
-	if len(p.Addr4) != 0 {
+	if len(p.PublicIP) != 0 {
-		if addr, ok := netip.AddrFromSlice(p.Addr4); ok {
+		addr, ok := netip.AddrFromSlice(p.PublicIP)
-			// Unmap so an IPv4-mapped form is stored canonically as 4 bytes.
+		if ok && addr.Is4() {
-			p.Addr4 = addr.Unmap().AsSlice()
+			p.PublicIP = addr.AsSlice()
-		}
-	}
-	if len(p.Addr6) != 0 {
-		if addr, ok := netip.AddrFromSlice(p.Addr6); ok {
-			p.Addr6 = addr.AsSlice()
 		}
 	}
 	if p.Port == 0 {
-		p.Port = 51820
+		p.Port = 456
 	}
 }
 
 func Peer_Validate(p *Peer) error {
-	if p.PeerIP < 1 || p.PeerIP > 254 {
+	if len(p.PublicIP) > 0 {
-		return ErrInvalidPeerIP
+		_, ok := netip.AddrFromSlice(p.PublicIP)
-	}
+		if !ok {
-	if len(p.Addr4) > 0 {
-		// Must be a genuine IPv4 address (reject an IPv6 in the v4 field).
-		if addr, ok := netip.AddrFromSlice(p.Addr4); !ok || !addr.Is4() {
-			return ErrInvalidIP
-		}
-	}
-	if len(p.Addr6) > 0 {
-		// Must be a genuine IPv6 address (reject IPv4 / IPv4-mapped in the v6 field).
-		if addr, ok := netip.AddrFromSlice(p.Addr6); !ok || !addr.Is6() || addr.Is4In6() {
 			return ErrInvalidIP
 		}
 	}
@@ -102,9 +88,6 @@ func Peer_Validate(p *Peer) error {
 		return ErrInvalidPort
 	}
 
-	if len(p.Name) == 0 {
-		return ErrInvalidPeerName
-	}
 	for _, c := range p.Name {
 		if c >= 'a' && c <= 'z' {
 			continue
@@ -112,9 +95,10 @@ func Peer_Validate(p *Peer) error {
 		if c >= '0' && c <= '9' {
 			continue
 		}
-		if c == '-' {
+		if c == '.' || c == '-' || c == '_' {
 			continue
 		}
+
 		return ErrInvalidPeerName
 	}
 

hub/api/db/tables.defs

@@ -3,21 +3,29 @@ TABLE config OF Config (
   Password    []byte
 );
 
+TABLE sessions OF Session NoUpdate (
+  SessionID  string PK,
+  CSRF       string,
+  SignedIn   bool,
+  CreatedAt  int64,
+  LastSeenAt int64
+);
+
 TABLE networks OF Network (
-  NetworkID   int64 PK,
+  NetworkID int64 PK,
-  LocalDomain string NoUpdate,
+  Name      string NoUpdate,
-  Network     []byte NoUpdate
+  Network   []byte NoUpdate
 );
 
 TABLE peers OF Peer (
   NetworkID  int64 PK,
   PeerIP     byte PK,
+  Version    int64,
   APIKey     string NoUpdate,
-  Name       string NoUpdate,
+  Name       string,
-  Addr4      []byte NoUpdate,
+  PublicIP   []byte,
-  Addr6      []byte NoUpdate,
+  Port       uint16,
-  Port       uint16 NoUpdate,
+  Relay      bool,
-  Relay      bool   NoUpdate,
+  PubKey     []byte NoUpdate,
-  WGPubKey   []byte NoUpdate,
+  PubSignKey []byte NoUpdate
-  SignPubKey []byte NoUpdate
 );

hub/api/db/written.go

@@ -1,5 +1,31 @@
 package db
 
+import "time"
+
+func Session_UpdateLastSeenAt(
+	tx TX,
+	id string,
+) (err error) {
+	_, err = tx.Exec("UPDATE sessions SET LastSeenAt=? WHERE SessionID=?", time.Now().Unix(), id)
+	return err
+}
+
+func Session_SetSignedIn(
+	tx TX,
+	id string,
+) (err error) {
+	_, err = tx.Exec("UPDATE sessions SET SignedIn=1 WHERE SessionID=?", id)
+	return err
+}
+
+func Session_DeleteBefore(
+	tx TX,
+	timestamp int64,
+) (err error) {
+	_, err = tx.Exec("DELETE FROM sessions WHERE LastSeenAt<?", timestamp)
+	return err
+}
+
 func Peer_ListAll(tx TX, networkID int64) ([]*Peer, error) {
 	const query = Peer_SelectQuery + ` WHERE NetworkID=? ORDER BY PeerIP ASC`
 	return Peer_List(tx, query, networkID)
@@ -11,3 +37,9 @@ func Peer_GetByAPIKey(tx TX, apiKey string) (*Peer, error) {
 		Peer_SelectQuery+` WHERE APIKey=?`,
 		apiKey)
 }
+
+func Peer_Exists(tx TX, networkID int64, ip byte) (exists bool, err error) {
+	const query = `SELECT EXISTS(SELECT 1 FROM peers WHERE NetworkID=? AND PeerIP=?)`
+	err = tx.QueryRow(query, networkID, ip).Scan(&exists)
+	return
+}

hub/api/errors.go

@@ -7,6 +7,7 @@ import (
 
 var (
 	ErrNotAuthorized = errors.New("not authorized")
+	ErrNoIPAvailable = errors.New("no IP address available")
 	ErrInvalidIP     = db.ErrInvalidIP
 	ErrInvalidPort   = db.ErrInvalidPort
 )

hub/api/migrations/2024-11-30-init.sql

@@ -3,23 +3,32 @@ CREATE TABLE config (
   Password    BLOB    NOT NULL  -- bcrypt password for web interface
 ) WITHOUT ROWID;
 
+CREATE TABLE sessions (
+  SessionID  TEXT    NOT NULL PRIMARY KEY,
+  CSRF       TEXT    NOT NULL,
+  SignedIn   INTEGER NOT NULL,
+  CreatedAt  INTEGER NOT NULL,
+  LastSeenAt INTEGER NOT NULL
+) WITHOUT ROWID;
+
+CREATE INDEX sessions_last_seen_index ON sessions(LastSeenAt);
+
 CREATE TABLE networks (
   NetworkID   INTEGER NOT NULL PRIMARY KEY,
-  LocalDomain TEXT    NOT NULL UNIQUE, -- Network/interface name.
+  Name        TEXT    NOT NULL UNIQUE, -- Network/interface name.
   Network     BLOB    NOT NULL UNIQUE  -- Network (/24), example 10.51.50.0
 ) WITHOUT ROWID;
 
 CREATE TABLE peers (
   NetworkID  INTEGER NOT NULL,
-  PeerIP     INTEGER NOT NULL,           -- Final byte of IP.
+  PeerIP     INTEGER NOT NULL,             -- Final byte of IP.
-  APIKey     TEXT    NOT NULL UNIQUE,    -- Peer's secret API key.
+  Version    INTEGER NOT NULL,             -- Changes when updated.
-  Name       TEXT    NOT NULL,           -- For humans.
+  APIKey     TEXT    NOT NULL UNIQUE,      -- Peer's secret API key.
-  Addr4      BLOB    NOT NULL,
+  Name       TEXT    NOT NULL UNIQUE,      -- For humans.
-  Addr6      BLOB    NOT NULL,
+  PublicIP   BLOB    NOT NULL,
   Port       INTEGER NOT NULL,
-  Relay      INTEGER NOT NULL DEFAULT 0, -- Boolean if peer will forward packets.
+  Relay      INTEGER NOT NULL DEFAULT 0,   -- Boolean if peer will forward packets. Must also have public address.
-  WGPubKey   BLOB    NOT NULL,
+  PubKey     BLOB    NOT NULL,
-  SignPubKey BLOB    NOT NULL,
+  PubSignKey BLOB    NOT NULL,
-  UNIQUE(NetworkID, Name),
   PRIMARY KEY(NetworkID, PeerIP)
 ) WITHOUT ROWID;

hub/api/types.go

@@ -3,12 +3,6 @@ package api
 import "vppn/hub/api/db"
 
 type Config = db.Config
+type Session = db.Session
 type Network = db.Network
 type Peer = db.Peer
-
-type Session struct {
-	SessionID  string
-	SignedIn   bool
-	CreatedAt  int64
-	LastSeenAt int64
-}

hub/app.go

@@ -2,7 +2,6 @@ package hub
 
 import (
 	"embed"
-	"encoding/base64"
 	"html/template"
 	"net/http"
 	"path/filepath"
@@ -48,19 +47,6 @@ func NewApp(conf Config) (*App, error) {
 	return app, nil
 }
 
-func (app *App) Handler() http.Handler {
-	cop := http.NewCrossOriginProtection()
-	return cop.Handler(app.mux)
-}
-
 var templateFuncs = template.FuncMap{
-	"ipToString":  ipBytesTostring,
+	"ipToString": ipBytesTostring,
-	"wgKeyString": wgKeyString,
-}
-
-func wgKeyString(key []byte) string {
-	if len(key) == 0 {
-		return "not set"
-	}
-	return base64.StdEncoding.EncodeToString(key)
 }

hub/cookie.go

@@ -2,6 +2,7 @@ package hub
 
 import (
 	"net/http"
+	"time"
 )
 
 func (a *App) getCookie(r *http.Request, name string) string {
@@ -25,12 +26,9 @@ func (a *App) setCookie(w http.ResponseWriter, name, value string) {
 
 func (a *App) deleteCookie(w http.ResponseWriter, name string) {
 	http.SetCookie(w, &http.Cookie{
-		Name:     name,
+		Name:    name,
-		Value:    "",
+		Value:   "",
-		Path:     "/",
+		Path:    "/",
-		Secure:   !a.insecure,
+		Expires: time.Unix(0, 0),
-		SameSite: http.SameSiteStrictMode,
-		HttpOnly: true,
-		MaxAge:   -1, // delete now
 	})
 }

hub/global.go

@@ -1,5 +1,5 @@
 package hub
 
 const (
-	sessionIDCookieName = "SessionID"
+	SESSION_ID_COOKIE_NAME = "SessionID"
 )

hub/handler.go

@@ -12,7 +12,7 @@ type handlerFunc func(s *api.Session, w http.ResponseWriter, r *http.Request) er
 
 func (app *App) handlePub(pattern string, fn handlerFunc) {
 	wrapped := func(w http.ResponseWriter, r *http.Request) {
-		sessionID := app.getCookie(r, sessionIDCookieName)
+		sessionID := app.getCookie(r, SESSION_ID_COOKIE_NAME)
 		s, err := app.api.Session_Get(sessionID)
 		if err != nil {
 			log.Printf("Failed to get session: %v", err)
@@ -20,13 +20,22 @@ func (app *App) handlePub(pattern string, fn handlerFunc) {
 			return
 		}
 
+		if s.SessionID != sessionID {
+			app.setCookie(w, SESSION_ID_COOKIE_NAME, s.SessionID)
+		}
+
 		if r.Method == http.MethodPost {
 			r.ParseMultipartForm(64 * 1024)
+			if r.FormValue("CSRF") != s.CSRF {
+				log.Printf("%s != %s", r.FormValue("CSRF"), s.CSRF)
+				http.Error(w, "CSRF mismatch", http.StatusBadRequest)
+				return
+			}
 		} else {
 			r.ParseForm()
 		}
 
-		if err := fn(&s, w, r); err != nil {
+		if err := fn(s, w, r); err != nil {
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 		}
 	}

hub/handlers.go

@@ -5,12 +5,13 @@ import (
 	"errors"
 	"log"
 	"net/http"
+	"net/netip"
+	"strings"
 	"vppn/hub/api"
 	"vppn/m"
 
 	"git.crumpington.com/lib/go/webutil"
 	"golang.org/x/crypto/bcrypt"
-	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
 )
 
 func (a *App) _root(s *api.Session, w http.ResponseWriter, r *http.Request) error {
@@ -34,11 +35,9 @@ func (a *App) _signinSubmit(s *api.Session, w http.ResponseWriter, r *http.Reque
 		return err
 	}
 
-	sess, err := a.api.Session_SignIn(pwd)
+	if err := a.api.Session_SignIn(s, pwd); err != nil {
-	if err != nil {
 		return err
 	}
-	a.setCookie(w, sessionIDCookieName, sess.SessionID)
 
 	return a.redirect(w, r, "/")
 }
@@ -51,7 +50,7 @@ func (a *App) _adminSignOutSubmit(s *api.Session, w http.ResponseWriter, r *http
 	if err := a.api.Session_Delete(s.SessionID); err != nil {
 		log.Printf("Failed to delete session cookie %s: %v", s.SessionID, err)
 	}
-	a.deleteCookie(w, sessionIDCookieName)
+	a.deleteCookie(w, SESSION_ID_COOKIE_NAME)
 	return a.redirect(w, r, "/")
 }
 
@@ -75,7 +74,7 @@ func (a *App) _adminNetworkCreateSubmit(s *api.Session, w http.ResponseWriter, r
 	var netStr string
 
 	err := webutil.NewFormScanner(r.Form).
-		Scan("LocalDomain", &n.LocalDomain).
+		Scan("Name", &n.Name).
 		Scan("Network", &netStr).
 		Error()
 	if err != nil {
@@ -145,15 +144,14 @@ func (a *App) _adminPeerCreate(s *api.Session, w http.ResponseWriter, r *http.Re
 }
 
 func (a *App) _adminPeerCreateSubmit(s *api.Session, w http.ResponseWriter, r *http.Request) error {
-	var addr4Str, addr6Str string
+	var ipStr string
 
 	p := &api.Peer{}
 	err := webutil.NewFormScanner(r.Form).
 		Scan("NetworkID", &p.NetworkID).
 		Scan("IP", &p.PeerIP).
 		Scan("Name", &p.Name).
-		Scan("Addr4", &addr4Str).
+		Scan("PublicIP", &ipStr).
-		Scan("Addr6", &addr6Str).
 		Scan("Port", &p.Port).
 		Scan("Relay", &p.Relay).
 		Error()
@@ -161,10 +159,7 @@ func (a *App) _adminPeerCreateSubmit(s *api.Session, w http.ResponseWriter, r *h
 		return err
 	}
 
-	if p.Addr4, err = stringToIP(addr4Str); err != nil {
+	if p.PublicIP, err = stringToIP(ipStr); err != nil {
-		return err
-	}
-	if p.Addr6, err = stringToIP(addr6Str); err != nil {
 		return err
 	}
 
@@ -187,6 +182,48 @@ func (a *App) _adminPeerView(s *api.Session, w http.ResponseWriter, r *http.Requ
 	}{s, net, peer})
 }
 
+func (a *App) _adminPeerEdit(s *api.Session, w http.ResponseWriter, r *http.Request) error {
+	net, peer, err := a.formGetPeer(r.Form)
+	if err != nil {
+		return err
+	}
+
+	return a.render("/network/peer-edit.html", w, struct {
+		Session *api.Session
+		Network *api.Network
+		Peer    *api.Peer
+	}{s, net, peer})
+}
+
+func (a *App) _adminPeerEditSubmit(s *api.Session, w http.ResponseWriter, r *http.Request) error {
+	_, peer, err := a.formGetPeer(r.Form)
+	if err != nil {
+		return err
+	}
+
+	var ipStr string
+
+	err = webutil.NewFormScanner(r.Form).
+		Scan("Name", &peer.Name).
+		Scan("PublicIP", &ipStr).
+		Scan("Port", &peer.Port).
+		Scan("Relay", &peer.Relay).
+		Error()
+	if err != nil {
+		return err
+	}
+
+	if peer.PublicIP, err = stringToIP(ipStr); err != nil {
+		return err
+	}
+
+	if err = a.api.Peer_Update(peer); err != nil {
+		return err
+	}
+
+	return a.redirect(w, r, "/admin/peer/view/?NetworkID=%d&PeerIP=%d", peer.NetworkID, peer.PeerIP)
+}
+
 func (a *App) _adminPeerDelete(s *api.Session, w http.ResponseWriter, r *http.Request) error {
 	n, peer, err := a.formGetPeer(r.Form)
 	if err != nil {
@@ -211,23 +248,40 @@ func (a *App) _adminPeerDeleteSubmit(s *api.Session, w http.ResponseWriter, r *h
 	return a.redirect(w, r, "/admin/network/view/?NetworkID=%d", n.NetworkID)
 }
 
+func (a *App) _adminNetworkHosts(s *api.Session, w http.ResponseWriter, r *http.Request) error {
+	n, peers, err := a.formGetNetworkPeers(r.Form)
+	if err != nil {
+		return err
+	}
+
+	b := strings.Builder{}
+
+	for _, peer := range peers {
+		ip := n.Network
+		ip[3] = peer.PeerIP
+		b.WriteString(netip.AddrFrom4([4]byte(ip)).String())
+		b.WriteString(" ")
+		b.WriteString(peer.Name)
+		b.WriteString("\n")
+	}
+
+	w.Write([]byte(b.String()))
+	return nil
+}
+
 func (a *App) _adminPasswordEdit(s *api.Session, w http.ResponseWriter, r *http.Request) error {
 	return a.render("/admin-password-edit.html", w, struct{ Session *api.Session }{s})
 }
 
 func (a *App) _adminPasswordSubmit(s *api.Session, w http.ResponseWriter, r *http.Request) error {
 	var (
+		conf    = a.api.Config_Get()
 		curPwd  string
 		newPwd  string
 		newPwd2 string
 	)
 
-	conf, err := a.api.Config_Get()
+	err := webutil.NewFormScanner(r.Form).
-	if err != nil {
-		return err
-	}
-
-	err = webutil.NewFormScanner(r.Form).
 		Scan("CurrentPassword", &curPwd).
 		Scan("NewPassword", &newPwd).
 		Scan("NewPassword2", &newPwd2).
@@ -264,25 +318,11 @@ func (a *App) _adminPasswordSubmit(s *api.Session, w http.ResponseWriter, r *htt
 }
 
 func (a *App) _peerInit(peer *api.Peer, w http.ResponseWriter, r *http.Request) error {
-	if len(peer.WGPubKey) != 0 {
-		http.Error(w, "Already initialized", http.StatusConflict)
-		return nil
-	}
-
 	args := m.PeerInitArgs{}
 	if err := json.NewDecoder(r.Body).Decode(&args); err != nil {
 		return err
 	}
 
-	if len(args.WGPubKey) != 32 {
-		http.Error(w, "invalid WGPubKey", http.StatusBadRequest)
-		return nil
-	}
-	if len(args.SignPubKey) != 32 {
-		http.Error(w, "invalid SignPubKey", http.StatusBadRequest)
-		return nil
-	}
-
 	net, err := a.api.Network_Get(peer.NetworkID)
 	if err != nil {
 		return err
@@ -293,12 +333,11 @@ func (a *App) _peerInit(peer *api.Peer, w http.ResponseWriter, r *http.Request)
 	}
 
 	resp := m.PeerInitResp{
-		PeerIP:      peer.PeerIP,
+		PeerIP:  peer.PeerIP,
-		Network:     net.Network,
+		Network: net.Network,
-		LocalDomain: net.LocalDomain,
 	}
 
-	resp.NetworkState.Peers, err = a.peersList(net.NetworkID)
+	resp.NetworkState.Peers, err = a.peersArray(net.NetworkID)
 	if err != nil {
 		return err
 	}
@@ -307,42 +346,34 @@ func (a *App) _peerInit(peer *api.Peer, w http.ResponseWriter, r *http.Request)
 }
 
 func (a *App) _peerFetchState(peer *api.Peer, w http.ResponseWriter, r *http.Request) error {
-	peers, err := a.peersList(peer.NetworkID)
+
+	peers, err := a.peersArray(peer.NetworkID)
 	if err != nil {
 		return err
 	}
 	return a.sendJSON(w, m.NetworkState{Peers: peers})
 }
 
-func (a *App) peersList(networkID int64) (peers []m.Peer, err error) {
+func (a *App) peersArray(networkID int64) (peers [256]*m.Peer, err error) {
 	l, err := a.api.Peer_List(networkID)
 	if err != nil {
-		return nil, err
+		return peers, err
 	}
 
-	peers = make([]m.Peer, 0, len(l))
-
 	for _, p := range l {
-		if len(p.WGPubKey) == 0 {
+		if len(p.PubKey) != 0 {
-			continue
+			peers[p.PeerIP] = &m.Peer{
+				PeerIP:     p.PeerIP,
+				Version:    p.Version,
+				Name:       p.Name,
+				PublicIP:   p.PublicIP,
+				Port:       p.Port,
+				Relay:      p.Relay,
+				PubKey:     p.PubKey,
+				PubSignKey: p.PubSignKey,
+			}
 		}
-		wgKey, err := wgtypes.NewKey(p.WGPubKey)
-		if err != nil {
-			continue // malformed key; skip rather than serve garbage
-		}
-		var signKey [32]byte
-		copy(signKey[:], p.SignPubKey)
-		peers = append(peers, m.Peer{
-			PeerIP:     p.PeerIP,
-			Name:       p.Name,
-			Addr4:      addrFromBytes(p.Addr4),
-			Addr6:      addrFromBytes(p.Addr6),
-			Port:       p.Port,
-			Relay:      p.Relay,
-			WGPubKey:   wgKey,
-			SignPubKey: signKey,
-		})
 	}
 
-	return peers, nil
+	return
 }

hub/main.go

@@ -31,7 +31,7 @@ func Main() {
 
 	srv := &http.Server{
 		Addr:    conf.ListenAddr,
-		Handler: app.Handler(),
+		Handler: app.mux,
 	}
 
 	log.Fatal(webutil.ListenAndServe(srv))

hub/routes.go

@@ -19,9 +19,12 @@ func (a *App) registerRoutes() {
 	a.handleSignedIn("POST /admin/network/delete/", a._adminNetworkDeleteSubmit)
 
 	a.handleSignedIn("GET  /admin/network/view/", a._adminNetworkView)
+	a.handleSignedIn("GET  /admin/network/hosts/", a._adminNetworkHosts)
 	a.handleSignedIn("GET  /admin/peer/create/", a._adminPeerCreate)
 	a.handleSignedIn("POST /admin/peer/create/", a._adminPeerCreateSubmit)
 	a.handleSignedIn("GET  /admin/peer/view/", a._adminPeerView)
+	a.handleSignedIn("GET  /admin/peer/edit/", a._adminPeerEdit)
+	a.handleSignedIn("POST /admin/peer/edit/", a._adminPeerEditSubmit)
 	a.handleSignedIn("GET  /admin/peer/delete/", a._adminPeerDelete)
 	a.handleSignedIn("POST /admin/peer/delete/", a._adminPeerDeleteSubmit)
 

hub/templates/admin-network-create.html

@@ -2,9 +2,10 @@
 <h2>Create Network</h2>
 
 <form method="POST">
-<p>
+  <input type="hidden" name="CSRF" value="{{.Session.CSRF}}">
-    <label>Local Domain (ending with .local)</label><br>
+  <p>
-    <input type="text" name="LocalDomain">
+    <label>Name</label><br>
+    <input type="text" name="Name">
   </p>
   <p>
     <label>Network /24</label><br>

hub/templates/admin-network-list.html

@@ -9,7 +9,7 @@
 <table>
   <thead>
     <tr>
-      <th>Local Domain</th>
+      <th>Name</th>
       <th>Network</th>
     </tr>
   </thead>
@@ -18,7 +18,7 @@
   <tr>
     <td>
       <a href="/admin/network/view/?NetworkID={{.NetworkID}}">
-        {{.LocalDomain}}
+        {{.Name}}
       </a>
     </td>
     <td>{{ipToString .Network}}</td>

hub/templates/admin-password-edit.html

@@ -2,7 +2,8 @@
 <h2>Change Password</h2>
 
 <form method="POST">
-<p>
+  <input type="hidden" name="CSRF" value="{{.Session.CSRF}}">
+  <p>
     <label>Current Password</label><br>
     <input type="password" name="CurrentPassword">
   </p>

hub/templates/admin-sign-out.html

@@ -2,7 +2,8 @@
 <h2>Sign Out</h2>
 
 <form method="POST">
-<p>
+  <input type="hidden" name="CSRF" value="{{.Session.CSRF}}">
+  <p>
     <button type="submit">Sign Out</button>
     <a href="/">Cancel</a>
   </p>

hub/templates/network/base.html

@@ -17,7 +17,7 @@
   </header>
   <h2>
     Network:
-    <a href="/admin/network/view/?NetworkID={{.Network.NetworkID}}">{{.Network.LocalDomain}}</a>
+    <a href="/admin/network/view/?NetworkID={{.Network.NetworkID}}">{{.Network.Name}}</a>
   </h2>
 
   {{block "body" .}}There's nothing here.{{end}}

hub/templates/network/network-delete.html

@@ -5,7 +5,8 @@
 <p>You must first delete all peers.</p>
 {{- else -}}
 <form method="POST">
-<input type="hidden" name="NetworkID" value="{{.Network.NetworkID}}">
+  <input type="hidden" name="CSRF" value="{{.Session.CSRF}}">
+  <input type="hidden" name="NetworkID" value="{{.Network.NetworkID}}">
   <p>
     <button type="submit">Delete</button>
     <a href="/admin/network/view/?NetworkID={{.Network.NetworkID}}">Cancel</a>

hub/templates/network/network-view.html

@@ -1,6 +1,7 @@
 {{define "body" -}}
 <p>
-  <a href="/admin/network/delete/?NetworkID={{.Network.NetworkID}}">Delete</a>
+  <a href="/admin/network/delete/?NetworkID={{.Network.NetworkID}}">Delete</a> /
+  <a href="/admin/network/hosts/?NetworkID={{.Network.NetworkID}}">Hosts</a>
 </p>
 
 <table class="def-list">
@@ -22,8 +23,7 @@
     <tr>
       <th>PeerIP</th>
       <th>Name</th>
-      <th>IPv4</th>
+      <th>Public IP</th>
-      <th>IPv6</th>
       <th>Port</th>
       <th>Relay</th>
     </tr>
@@ -37,8 +37,7 @@
       </a>
     </td>
     <td>{{.Name}}</td>
-    <td>{{ipToString .Addr4}}</td>
+    <td>{{ipToString .PublicIP}}</td>
-    <td>{{ipToString .Addr6}}</td>
     <td>{{.Port}}</td>
     <td>{{if .Relay}}T{{else}}F{{end}}</td>
   </tr>

hub/templates/network/peer-create.html

@@ -2,6 +2,7 @@
 <h3>New Peer</h3>
 
 <form method="POST">
+  <input type="hidden" name="CSRF" value="{{.Session.CSRF}}">
   <input type="hidden" name="NetworkID" value="{{.Network.NetworkID}}">
   <p>
     <label>IP</label><br>
@@ -12,16 +13,12 @@
     <input type="text" name="Name">
   </p>
   <p>
-    <label>IPv4 Address (optional)</label><br>
+    <label>Public IP</label><br>
-    <input type="text" name="Addr4">
+    <input type="text" name="PublicIP">
   </p>
   <p>
-    <label>IPv6 Address (optional)</label><br>
+    <label>Port</label><br>
-    <input type="text" name="Addr6">
+    <input type="number" name="Port" value="456">
-  </p>
-  <p>
-    <label>WireGuard Port</label><br>
-    <input type="number" name="Port" value="51820">
   </p>
   <p>
     <label>

hub/templates/network/peer-delete.html

@@ -3,8 +3,9 @@
 
 {{with .Peer -}}
 <form method="POST">
-<input type="hidden" name="NetworkID" value="{{.NetworkID}}">
+  <input type="hidden" name="CSRF" value="{{$.Session.CSRF}}">
-  <input type="hidden" name="PeerIP" value="{{.PeerIP}}">
+  <input type="hidden" name="NetworkID" value="{{.NetworkID}}">
+  <input type="hidden" name="NetworkID" value="{{.PeerIP}}">
   <p>
     <button type="submit">Delete</button>
     <a href="/admin/peer/view/?PeerIP={{.PeerIP}}&NetworkID={{.NetworkID}}">Cancel</a>

hub/templates/network/peer-edit.html

@@ -0,0 +1,35 @@
+{{define "body" -}}
+<h2>Edit Peer</h2>
+
+{{with .Peer -}}
+<form method="POST">
+  <input type="hidden" name="CSRF" value="{{$.Session.CSRF}}">
+  <p>
+    <label>Peer IP</label><br>
+    <input type="text" value="{{.PeerIP}}" disabled>
+  </p>
+  <p>
+    <label>Name</label><br>
+    <input type="text" name="Name" value="{{.Name}}">
+  </p>
+  <p>
+    <label>Public IP</label><br>
+    <input type="text" name="PublicIP" value="{{ipToString .PublicIP}}">
+  </p>
+  <p>
+    <label>Port</label><br>
+    <input type="number" name="Port" value="{{.Port}}">
+  </p>
+  <p>
+    <label>
+      <input type="checkbox" name="Relay" {{if .Relay}}checked{{end}}>
+      Relay
+    </label>
+  </p>
+  <p>
+    <button type="submit">Save</button>
+    <a href="/admin/peer/view/?NetworkID={{$.Network.NetworkID}}&PeerIP={{.PeerIP}}">Cancel</a>
+  </p>
+</form>
+{{- end}}
+{{- end}}

hub/templates/network/peer-view.html

@@ -1,17 +1,17 @@
 {{define "body" -}}
 <h3>{{.Peer.Name}}</h3>
 <p>
+  <a href="/admin/peer/edit/?NetworkID={{.Network.NetworkID}}&PeerIP={{.Peer.PeerIP}}">Edit</a> /
   <a href="/admin/peer/delete/?NetworkID={{.Network.NetworkID}}&PeerIP={{.Peer.PeerIP}}">Delete</a>
 </p>
 
 {{with .Peer -}}
 <table class="def-list">
   <tr><td>Peer IP</td><td>{{.PeerIP}}</td></tr>
-  <tr><td>IPv4 Address</td><td>{{ipToString .Addr4}}</td></tr>
+  <tr><td>Public IP</td><td>{{ipToString .PublicIP}}</td></tr>
-  <tr><td>IPv6 Address</td><td>{{ipToString .Addr6}}</td></tr>
+  <tr><td>Port</td><td>{{.Port}}</td></tr>
-  <tr><td>WireGuard Port</td><td>{{.Port}}</td></tr>
   <tr><td>Relay</td><td>{{if .Relay}}T{{else}}F{{end}}</td></tr>
-  <tr><td>WG Public Key</td><td>{{wgKeyString .WGPubKey}}</td></tr>
+</td></tr>
 </table>
 
 <details>
@@ -19,6 +19,7 @@
   <p>{{.APIKey}}</p>
 </details>
 
+
 {{- end}}
 
 {{- end}}

hub/templates/sign-in.html

@@ -2,7 +2,8 @@
 <h2>Sign In</h2>
 
 <form method="POST">
-<p>
+  <input type="hidden" name="CSRF" value="{{.Session.CSRF}}">
+  <p>
     <label>Password</label><br>
     <input type="password" name="Password">
   </p>

hub/util.go

@@ -38,19 +38,6 @@ func (app *App) sendJSON(w http.ResponseWriter, data any) error {
 	return nil
 }
 
-// addrFromBytes parses raw IP bytes (4 or 16) into a netip.Addr, unmapping
-// IPv4-in-IPv6, returning the zero Addr for empty/invalid input.
-func addrFromBytes(b []byte) netip.Addr {
-	if len(b) == 0 {
-		return netip.Addr{}
-	}
-	addr, ok := netip.AddrFromSlice(b)
-	if !ok {
-		return netip.Addr{}
-	}
-	return addr.Unmap()
-}
-
 func stringToIP(in string) ([]byte, error) {
 	in = strings.TrimSpace(in)
 	if len(in) == 0 {

m/models.go

@@ -1,133 +1,28 @@
 // The package `m` contains models shared between the hub and peer programs.
 package m
 
-import (
-	"encoding/base64"
-	"encoding/json"
-	"fmt"
-	"net/netip"
-
-	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
-)
-
 type PeerInitArgs struct {
-	WGPubKey   []byte
+	EncPubKey  []byte
-	SignPubKey []byte
+	PubSignKey []byte
 }
 
 type PeerInitResp struct {
 	PeerIP       byte
 	Network      []byte
-	LocalDomain  string
 	NetworkState NetworkState
 }
 
-// Peer is the network membership record for a single peer, exchanged between
-// the hub and peers. Addr4/Addr6 are the peer's public endpoint addresses (zero
-// if it has none); Port is its WireGuard listen port, meaningful even for a
-// non-public peer (it is the peer's own bind/beacon port).
 type Peer struct {
 	PeerIP     byte
+	Version    int64
 	Name       string
-	Addr4      netip.Addr // zero if none
+	PublicIP   []byte
-	Addr6      netip.Addr // zero if none
 	Port       uint16
 	Relay      bool
-	WGPubKey   wgtypes.Key
+	PubKey     []byte
-	SignPubKey [32]byte
+	PubSignKey []byte
-}
-
-// IsPublic reports whether the peer advertises at least one reachable endpoint.
-func (p Peer) IsPublic() bool {
-	return p.Addr4.IsValid() || p.Addr6.IsValid()
-}
-
-// Endpoint4 returns the IPv4 endpoint (addr+port), or the zero AddrPort if the
-// peer has no IPv4 address.
-func (p Peer) Endpoint4() netip.AddrPort {
-	if !p.Addr4.IsValid() {
-		return netip.AddrPort{}
-	}
-	return netip.AddrPortFrom(p.Addr4, p.Port)
-}
-
-// Endpoint6 returns the IPv6 endpoint (addr+port), or the zero AddrPort if the
-// peer has no IPv6 address.
-func (p Peer) Endpoint6() netip.AddrPort {
-	if !p.Addr6.IsValid() {
-		return netip.AddrPort{}
-	}
-	return netip.AddrPortFrom(p.Addr6, p.Port)
-}
-
-// PreferredEndpoint returns the IPv4 endpoint if present, else IPv6.
-func (p Peer) PreferredEndpoint() netip.AddrPort {
-	if ep := p.Endpoint4(); ep.IsValid() {
-		return ep
-	}
-	return p.Endpoint6()
-}
-
-// peerJSON is the wire representation. netip.Addr fields round-trip as text
-// strings automatically; only the fixed-size key arrays need base64 (otherwise
-// encoding/json would emit them as arrays of numbers).
-type peerJSON struct {
-	PeerIP     byte
-	Name       string
-	Addr4      netip.Addr
-	Addr6      netip.Addr
-	Port       uint16
-	Relay      bool
-	WGPubKey   string
-	SignPubKey string
-}
-
-func (p Peer) MarshalJSON() ([]byte, error) {
-	return json.Marshal(peerJSON{
-		PeerIP:     p.PeerIP,
-		Name:       p.Name,
-		Addr4:      p.Addr4,
-		Addr6:      p.Addr6,
-		Port:       p.Port,
-		Relay:      p.Relay,
-		WGPubKey:   base64.StdEncoding.EncodeToString(p.WGPubKey[:]),
-		SignPubKey: base64.StdEncoding.EncodeToString(p.SignPubKey[:]),
-	})
-}
-
-func (p *Peer) UnmarshalJSON(data []byte) error {
-	var j peerJSON
-	if err := json.Unmarshal(data, &j); err != nil {
-		return err
-	}
-	wg, err := base64.StdEncoding.DecodeString(j.WGPubKey)
-	if err != nil {
-		return fmt.Errorf("decode WGPubKey: %w", err)
-	}
-	key, err := wgtypes.NewKey(wg)
-	if err != nil {
-		return fmt.Errorf("invalid WGPubKey: %w", err)
-	}
-	sign, err := base64.StdEncoding.DecodeString(j.SignPubKey)
-	if err != nil {
-		return fmt.Errorf("decode SignPubKey: %w", err)
-	}
-	if len(sign) != 32 {
-		return fmt.Errorf("invalid SignPubKey length: %d", len(sign))
-	}
-	*p = Peer{
-		PeerIP:     j.PeerIP,
-		Name:       j.Name,
-		Addr4:      j.Addr4,
-		Addr6:      j.Addr6,
-		Port:       j.Port,
-		Relay:      j.Relay,
-		WGPubKey:   key,
-		SignPubKey: [32]byte(sign),
-	}
-	return nil
 }
 
 type NetworkState struct {
-	Peers []Peer
+	Peers [256]*Peer
 }

peer/app.go

@@ -1,105 +0,0 @@
-package peer
-
-import (
-	"net/netip"
-	"os"
-	"os/signal"
-	"syscall"
-	"time"
-
-	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
-
-	"vppn/m"
-	"vppn/peer/control"
-	"vppn/peer/multicast"
-	"vppn/peer/wginterface"
-)
-
-var _ WGDevice = (*wginterface.Device)(nil) // compile-time check: Device satisfies WGDevice
-
-const (
-	ControlPort     = 4561
-	PingInterval    = 8 * time.Second
-	TimeoutInterval = 30 * time.Second
-)
-
-// scratchSize is large enough for the biggest buffer either the ping or the
-// multicast path serializes through the shared App scratch.
-const scratchSize = max(control.Size, multicast.SignedPacketSize)
-
-type PingEvent struct {
-	srcVPNIP netip.Addr
-	ping     control.Ping
-}
-
-// App is the peer application. All mutable state lives here and is
-// accessed only from the Run goroutine.
-type App struct {
-	// Identity
-	vpnIP       netip.Addr
-	vpnNet      netip.Prefix
-	privKey     wgtypes.Key
-	pubKey      wgtypes.Key
-	isRelay     bool
-	isPublic    bool
-	localDomain string
-
-	// Infrastructure
-	dev         WGDevice
-	controlConn ControlConn
-
-	// Peer state
-	relay      *Peer
-	peersByKey map[wgtypes.Key]*Peer
-	peersByIP  map[netip.Addr]*Peer
-
-	// Our own external endpoints, learned from Dst fields in incoming pings
-	selfV4 netip.AddrPort
-	selfV6 netip.AddrPort
-
-	// Reusable serialization scratch for outgoing pings and multicast signature
-	// verification. Only touched from the Run goroutine.
-	scratch []byte
-
-	// Event channels fed by background goroutines
-	hubAddCh    <-chan m.Peer
-	hubRemoveCh <-chan wgtypes.Key
-	pingCh      <-chan PingEvent
-	multicastCh <-chan multicast.Packet
-}
-
-// Run is the main event loop. It runs until SIGTERM/SIGINT.
-func (a *App) Run() error {
-	// Establish a clean hosts section before the first poll lands, clearing
-	// any stale entries left by a prior run (e.g. crash, or peers removed
-	// while we were down).
-	a.updateHosts()
-
-	ticker := time.NewTicker(PingInterval)
-	defer ticker.Stop()
-
-	sig := make(chan os.Signal, 1)
-	signal.Notify(sig, syscall.SIGTERM, syscall.SIGINT)
-	defer signal.Stop(sig)
-
-	for {
-		select {
-		case p := <-a.hubAddCh:
-			a.onAddPeer(p)
-		case key := <-a.hubRemoveCh:
-			a.onRemovePeer(key)
-		case e := <-a.pingCh:
-			a.onPing(e)
-		case e := <-a.multicastCh:
-			a.onMulticastDiscovery(e)
-		case <-ticker.C:
-			a.onTick()
-		case <-sig:
-			return a.onShutdown()
-		}
-	}
-}
-
-func (a *App) onShutdown() error {
-	return wginterface.Delete(a.dev.Name())
-}

peer/app_test.go

@@ -1,62 +0,0 @@
-package peer
-
-import (
-	"net/netip"
-	"testing"
-	"time"
-
-	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
-
-	"vppn/m"
-	"vppn/peer/multicast"
-)
-
-// addRelayPeer adds a public relay peer and marks it Up so it satisfies
-// CanRelay. It does not set a.relay — callers do that explicitly.
-func addRelayPeer(t *testing.T, a *App, vpnIP string, ep netip.AddrPort) *Peer {
-	t.Helper()
-	key := mustKey(t)
-	ip := netip.MustParseAddr(vpnIP)
-	a.onAddPeer(m.Peer{
-		WGPubKey: key,
-		PeerIP:   ip.As4()[3],
-		Addr4:    ep.Addr(),
-		Port:     ep.Port(),
-		Relay:    true,
-	})
-	p := a.peersByKey[key]
-	p.wgPeer.LastHandshakeTime = time.Now()
-	return p
-}
-
-// newTestApp returns a minimal App wired to a fakeWGDevice and fakeControlConn.
-// vpnIP is the local VPN address (e.g. "10.0.0.1").
-// isPublic / isRelay describe the local node's role.
-func newTestApp(t *testing.T, vpnIP string, isPublic, isRelay bool) (*App, *fakeWGDevice, *fakeControlConn) {
-	t.Helper()
-	privKey, err := wgtypes.GeneratePrivateKey()
-	if err != nil {
-		t.Fatalf("generate key: %v", err)
-	}
-	ip := netip.MustParseAddr(vpnIP)
-	dev := &fakeWGDevice{}
-	cc := &fakeControlConn{}
-	a := &App{
-		vpnIP:       ip,
-		vpnNet:      netip.MustParsePrefix("10.0.0.0/24"),
-		privKey:     privKey,
-		pubKey:      privKey.PublicKey(),
-		isPublic:    isPublic,
-		isRelay:     isRelay,
-		dev:         dev,
-		controlConn: cc,
-		peersByKey:  make(map[wgtypes.Key]*Peer),
-		peersByIP:   make(map[netip.Addr]*Peer),
-		scratch:     make([]byte, scratchSize),
-		hubAddCh:    make(chan m.Peer),
-		hubRemoveCh: make(chan wgtypes.Key),
-		pingCh:      make(chan PingEvent),
-		multicastCh: make(chan multicast.Packet),
-	}
-	return a, dev, cc
-}

peer/bitset.go

@@ -0,0 +1,21 @@
+package peer
+
+const bitSetSize = 512 // Multiple of 64.
+
+type bitSet [bitSetSize / 64]uint64
+
+func (bs *bitSet) Set(i int) {
+	bs[i/64] |= 1 << (i % 64)
+}
+
+func (bs *bitSet) Clear(i int) {
+	bs[i/64] &= ^(1 << (i % 64))
+}
+
+func (bs *bitSet) ClearAll() {
+	clear(bs[:])
+}
+
+func (bs *bitSet) Get(i int) bool {
+	return bs[i/64]&(1<<(i%64)) != 0
+}

peer/bitset_test.go

@@ -0,0 +1,48 @@
+package peer
+
+import (
+	"math/rand"
+	"testing"
+)
+
+func TestBitSet(t *testing.T) {
+	state := make([]bool, bitSetSize)
+	for i := range state {
+		state[i] = rand.Float32() > 0.5
+	}
+
+	bs := bitSet{}
+
+	for i := range state {
+		if state[i] {
+			bs.Set(i)
+		}
+	}
+
+	for i := range state {
+		if bs.Get(i) != state[i] {
+			t.Fatal(i, state[i], bs.Get(i))
+		}
+	}
+
+	for i := range state {
+		if rand.Float32() > 0.5 {
+			state[i] = false
+			bs.Clear(i)
+		}
+	}
+
+	for i := range state {
+		if bs.Get(i) != state[i] {
+			t.Fatal(i, state[i], bs.Get(i))
+		}
+	}
+
+	bs.ClearAll()
+
+	for i := range state {
+		if bs.Get(i) {
+			t.Fatal(i, bs.Get(i))
+		}
+	}
+}

peer/cipher-control.go

@@ -0,0 +1,26 @@
+package peer
+
+import "golang.org/x/crypto/nacl/box"
+
+type controlCipher struct {
+	sharedKey [32]byte
+}
+
+func newControlCipher(privKey, pubKey []byte) *controlCipher {
+	shared := [32]byte{}
+	box.Precompute(&shared, (*[32]byte)(pubKey), (*[32]byte)(privKey))
+	return &controlCipher{shared}
+}
+
+func (cc *controlCipher) Encrypt(h Header, data, out []byte) []byte {
+	const s = controlHeaderSize
+	out = out[:s+controlCipherOverhead+len(data)]
+	h.Marshal(out[:s])
+	box.SealAfterPrecomputation(out[s:s], data, (*[24]byte)(out[:s]), &cc.sharedKey)
+	return out
+}
+
+func (cc *controlCipher) Decrypt(encrypted, out []byte) (data []byte, ok bool) {
+	const s = controlHeaderSize
+	return box.OpenAfterPrecomputation(out[:0], encrypted[s:], (*[24]byte)(encrypted[:s]), &cc.sharedKey)
+}

peer/cipher-control_test.go

@@ -0,0 +1,122 @@
+package peer
+
+import (
+	"bytes"
+	"crypto/rand"
+	"reflect"
+	"testing"
+
+	"golang.org/x/crypto/nacl/box"
+)
+
+func newControlCipherForTesting() (c1, c2 *controlCipher) {
+	pubKey1, privKey1, err := box.GenerateKey(rand.Reader)
+	if err != nil {
+		panic(err)
+	}
+
+	pubKey2, privKey2, err := box.GenerateKey(rand.Reader)
+	if err != nil {
+		panic(err)
+	}
+
+	return newControlCipher(privKey1[:], pubKey2[:]),
+		newControlCipher(privKey2[:], pubKey1[:])
+}
+
+func TestControlCipher(t *testing.T) {
+	c1, c2 := newControlCipherForTesting()
+
+	maxSizePlaintext := make([]byte, bufferSize-controlHeaderSize-controlCipherOverhead)
+	rand.Read(maxSizePlaintext)
+
+	testCases := [][]byte{
+		make([]byte, 0),
+		{1},
+		{255},
+		{1, 2, 3, 4, 5},
+		[]byte("Hello world"),
+		maxSizePlaintext,
+	}
+
+	for _, plaintext := range testCases {
+		h1 := Header{
+			StreamID: controlStreamID,
+			Counter:  235153,
+			SourceIP: 4,
+			DestIP:   88,
+		}
+
+		encrypted := make([]byte, bufferSize)
+
+		encrypted = c1.Encrypt(h1, plaintext, encrypted)
+
+		h2 := Header{}
+		h2.Parse(encrypted)
+		if !reflect.DeepEqual(h1, h2) {
+			t.Fatal(h1, h2)
+		}
+
+		decrypted, ok := c2.Decrypt(encrypted, make([]byte, bufferSize))
+		if !ok {
+			t.Fatal(ok)
+		}
+
+		if !bytes.Equal(decrypted, plaintext) {
+			t.Fatal("not equal")
+		}
+	}
+}
+
+func TestControlCipher_ShortCiphertext(t *testing.T) {
+	c1, _ := newControlCipherForTesting()
+	shortText := make([]byte, controlHeaderSize+controlCipherOverhead-1)
+	rand.Read(shortText)
+	_, ok := c1.Decrypt(shortText, make([]byte, bufferSize))
+	if ok {
+		t.Fatal(ok)
+	}
+}
+
+func BenchmarkControlCipher_Encrypt(b *testing.B) {
+	c1, _ := newControlCipherForTesting()
+	h1 := Header{
+		Counter:  235153,
+		SourceIP: 4,
+		DestIP:   88,
+	}
+
+	plaintext := make([]byte, bufferSize-controlHeaderSize-controlCipherOverhead)
+	rand.Read(plaintext)
+
+	encrypted := make([]byte, bufferSize)
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		encrypted = c1.Encrypt(h1, plaintext, encrypted)
+	}
+}
+
+func BenchmarkControlCipher_Decrypt(b *testing.B) {
+	c1, c2 := newControlCipherForTesting()
+
+	h1 := Header{
+		Counter:  235153,
+		SourceIP: 4,
+		DestIP:   88,
+	}
+
+	plaintext := make([]byte, bufferSize-controlHeaderSize-controlCipherOverhead)
+	rand.Read(plaintext)
+
+	encrypted := make([]byte, bufferSize)
+
+	encrypted = c1.Encrypt(h1, plaintext, encrypted)
+
+	decrypted := make([]byte, bufferSize)
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		decrypted, _ = c2.Decrypt(encrypted, decrypted)
+	}
+}

peer/cipher-data.go

@@ -0,0 +1,61 @@
+package peer
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/rand"
+	"log"
+)
+
+type dataCipher struct {
+	key  [32]byte
+	aead cipher.AEAD
+}
+
+func newDataCipher() *dataCipher {
+	key := [32]byte{}
+	if _, err := rand.Read(key[:]); err != nil {
+		log.Fatalf("Failed to read random data: %v", err)
+	}
+	return newDataCipherFromKey(key)
+}
+
+func newDataCipherFromKey(key [32]byte) *dataCipher {
+	block, err := aes.NewCipher(key[:])
+	if err != nil {
+		log.Fatalf("Failed to create new cipher: %v", err)
+	}
+
+	aead, err := cipher.NewGCM(block)
+	if err != nil {
+		log.Fatalf("Failed to create new GCM: %v", err)
+	}
+
+	return &dataCipher{key: key, aead: aead}
+}
+
+func (sc *dataCipher) Key() [32]byte {
+	return sc.key
+}
+
+func (sc *dataCipher) Encrypt(h Header, data, out []byte) []byte {
+	const s = dataHeaderSize
+	out = out[:s+dataCipherOverhead+len(data)]
+	h.Marshal(out[:s])
+	sc.aead.Seal(out[s:s], out[:s], data, nil)
+	return out
+}
+
+func (sc *dataCipher) Decrypt(encrypted, out []byte) (data []byte, ok bool) {
+	const s = dataHeaderSize
+	if len(encrypted) < s+dataCipherOverhead {
+		ok = false
+		return
+	}
+
+	var err error
+
+	data, err = sc.aead.Open(out[:0], encrypted[:s], encrypted[s:], nil)
+	ok = err == nil
+	return
+}

peer/cipher-data_test.go

@@ -0,0 +1,141 @@
+package peer
+
+import (
+	"bytes"
+	"crypto/rand"
+	mrand "math/rand/v2"
+	"reflect"
+	"testing"
+)
+
+func TestDataCipher(t *testing.T) {
+	maxSizePlaintext := make([]byte, bufferSize-dataHeaderSize-dataCipherOverhead)
+	rand.Read(maxSizePlaintext)
+
+	testCases := [][]byte{
+		make([]byte, 0),
+		{1},
+		{255},
+		{1, 2, 3, 4, 5},
+		[]byte("Hello world"),
+		maxSizePlaintext,
+	}
+
+	for _, plaintext := range testCases {
+		h1 := Header{
+			StreamID: dataStreamID,
+			Counter:  235153,
+			SourceIP: 4,
+			DestIP:   88,
+		}
+
+		encrypted := make([]byte, bufferSize)
+
+		dc1 := newDataCipher()
+		encrypted = dc1.Encrypt(h1, plaintext, encrypted)
+		h2 := Header{}
+		h2.Parse(encrypted)
+
+		dc2 := newDataCipherFromKey(dc1.Key())
+
+		decrypted, ok := dc2.Decrypt(encrypted, make([]byte, bufferSize-dataHeaderSize))
+		if !ok {
+			t.Fatal(ok)
+		}
+
+		if !bytes.Equal(plaintext, decrypted) {
+			t.Fatal("not equal")
+		}
+
+		if !reflect.DeepEqual(h1, h2) {
+			t.Fatalf("%v != %v", h1, h2)
+		}
+	}
+}
+
+func TestDataCipher_ModifyCiphertext(t *testing.T) {
+	maxSizePlaintext := make([]byte, bufferSize-dataHeaderSize-dataCipherOverhead)
+	rand.Read(maxSizePlaintext)
+
+	testCases := [][]byte{
+		make([]byte, 0),
+		{1},
+		{255},
+		{1, 2, 3, 4, 5},
+		[]byte("Hello world"),
+		maxSizePlaintext,
+	}
+
+	for _, plaintext := range testCases {
+		h1 := Header{
+			Counter:  235153,
+			SourceIP: 4,
+			DestIP:   88,
+		}
+
+		encrypted := make([]byte, bufferSize)
+
+		dc1 := newDataCipher()
+		encrypted = dc1.Encrypt(h1, plaintext, encrypted)
+		encrypted[mrand.IntN(len(encrypted))]++
+
+		dc2 := newDataCipherFromKey(dc1.Key())
+
+		_, ok := dc2.Decrypt(encrypted, make([]byte, bufferSize-dataHeaderSize))
+		if ok {
+			t.Fatal(ok)
+		}
+	}
+}
+
+func TestDataCipher_ShortCiphertext(t *testing.T) {
+	dc1 := newDataCipher()
+	shortText := make([]byte, dataHeaderSize+dataCipherOverhead-1)
+	rand.Read(shortText)
+	_, ok := dc1.Decrypt(shortText, make([]byte, bufferSize))
+	if ok {
+		t.Fatal(ok)
+	}
+}
+
+func BenchmarkDataCipher_Encrypt(b *testing.B) {
+	h1 := Header{
+		Counter:  235153,
+		SourceIP: 4,
+		DestIP:   88,
+	}
+
+	plaintext := make([]byte, bufferSize-dataHeaderSize-dataCipherOverhead)
+	rand.Read(plaintext)
+
+	encrypted := make([]byte, bufferSize)
+
+	dc1 := newDataCipher()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		encrypted = dc1.Encrypt(h1, plaintext, encrypted)
+	}
+}
+
+func BenchmarkDataCipher_Decrypt(b *testing.B) {
+	h1 := Header{
+		Counter:  235153,
+		SourceIP: 4,
+		DestIP:   88,
+	}
+
+	plaintext := make([]byte, bufferSize-dataHeaderSize-dataCipherOverhead)
+	rand.Read(plaintext)
+
+	encrypted := make([]byte, bufferSize)
+
+	dc1 := newDataCipher()
+	encrypted = dc1.Encrypt(h1, plaintext, encrypted)
+
+	decrypted := make([]byte, bufferSize)
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		decrypted, _ = dc1.Decrypt(encrypted, decrypted)
+	}
+}

peer/connreader.go

@@ -0,0 +1,46 @@
+package peer
+
+import (
+	"log"
+	"net"
+	"net/netip"
+)
+
+type ConnReader struct {
+	Globals
+	conn *net.UDPConn
+	buf  []byte
+}
+
+func NewConnReader(g Globals, conn *net.UDPConn) *ConnReader {
+	return &ConnReader{
+		Globals: g,
+		conn:    conn,
+		buf:     make([]byte, bufferSize),
+	}
+}
+
+func (r *ConnReader) Run() {
+	for {
+		r.handleNextPacket()
+	}
+}
+
+func (r *ConnReader) handleNextPacket() {
+	buf := r.buf[:bufferSize]
+	n, remoteAddr, err := r.conn.ReadFromUDPAddrPort(buf)
+	if err != nil {
+		log.Fatalf("Failed to read from UDP port: %v", err)
+	}
+
+	if n < headerSize {
+		return
+	}
+
+	remoteAddr = netip.AddrPortFrom(remoteAddr.Addr().Unmap(), remoteAddr.Port())
+
+	buf = buf[:n]
+	h := parseHeader(buf)
+
+	r.RemotePeers[h.SourceIP].Load().HandlePacket(h, remoteAddr, buf)
+}

peer/control/ping.go

@@ -1,76 +0,0 @@
-// Package control implements the VPN-internal peer control protocol.
-// Peers exchange Ping packets over UDP on the VPN control port to maintain
-// liveness and discover external endpoints for direct connection attempts.
-package control
-
-import (
-	"encoding/binary"
-	"fmt"
-	"net/netip"
-)
-
-const (
-	version = 1
-	Size    = 51 // 1 version + 8 PingTS + 6 SrcV4 + 18 SrcV6 + 18 Dst
-)
-
-// Ping is the single control packet type exchanged between VPN peers.
-//
-// In each peer pair, the peer with the lower VPN IP is the client: it sets
-// PingTS and sends pings on a timer. The server echoes PingTS back in its
-// response, allowing the client to compute RTT = now - PingTS.
-//
-// Both client and server populate SrcV4, SrcV6, and Dst on every packet so
-// endpoint information flows in both directions.
-//
-// Dst is the recipient's external endpoint as observed by the sender from the
-// WireGuard handshake source. Zero if the sender has not observed a handshake
-// from the recipient.
-type Ping struct {
-	PingTS int64          // Client ping send time in nanoseconds.
-	SrcV4  netip.AddrPort // Sender's discovered IPv4 address and port.
-	SrcV6  netip.AddrPort // Sender's discovered IPv6 address and port.
-	Dst    netip.AddrPort
-}
-
-// Marshal encodes p into buf (which must be at least Size bytes) and returns
-// buf[:Size]. Taking the buffer lets callers reuse one across sends; every
-// field is written unconditionally so a reused buffer needs no pre-zeroing.
-func (p Ping) Marshal(buf []byte) []byte {
-	buf[0] = version
-	binary.BigEndian.PutUint64(buf[1:9], uint64(p.PingTS))
-	if p.SrcV4.IsValid() {
-		a4 := p.SrcV4.Addr().As4()
-		copy(buf[9:13], a4[:])
-		binary.BigEndian.PutUint16(buf[13:15], p.SrcV4.Port())
-	} else {
-		clear(buf[9:15])
-	}
-	a16 := p.SrcV6.Addr().As16()
-	copy(buf[15:31], a16[:])
-	binary.BigEndian.PutUint16(buf[31:33], p.SrcV6.Port())
-	a16 = p.Dst.Addr().As16()
-	copy(buf[33:49], a16[:])
-	binary.BigEndian.PutUint16(buf[49:51], p.Dst.Port())
-	return buf[:Size]
-}
-
-// Unmarshal decodes a Ping from a fixed-size 51-byte array.
-func Unmarshal(buf [Size]byte) (Ping, error) {
-	if buf[0] != version {
-		return Ping{}, fmt.Errorf("unknown ping version %d", buf[0])
-	}
-	p := Ping{
-		PingTS: int64(binary.BigEndian.Uint64(buf[1:9])),
-	}
-	if addr := netip.AddrFrom4([4]byte(buf[9:13])); !addr.IsUnspecified() {
-		p.SrcV4 = netip.AddrPortFrom(addr, binary.BigEndian.Uint16(buf[13:15]))
-	}
-	if addr := netip.AddrFrom16([16]byte(buf[15:31])); !addr.IsUnspecified() {
-		p.SrcV6 = netip.AddrPortFrom(addr, binary.BigEndian.Uint16(buf[31:33]))
-	}
-	if addr := netip.AddrFrom16([16]byte(buf[33:49])).Unmap(); !addr.IsUnspecified() {
-		p.Dst = netip.AddrPortFrom(addr, binary.BigEndian.Uint16(buf[49:51]))
-	}
-	return p, nil
-}

peer/control/ping_test.go

@@ -1,106 +0,0 @@
-package control_test
-
-import (
-	"net/netip"
-	"testing"
-
-	"vppn/peer/control"
-)
-
-func TestRoundTrip(t *testing.T) {
-	cases := []struct {
-		name string
-		ping control.Ping
-	}{
-		{
-			name: "zero",
-			ping: control.Ping{},
-		},
-		{
-			name: "client ping",
-			ping: control.Ping{
-				PingTS: 1234567890,
-				SrcV4:  netip.MustParseAddrPort("1.2.3.4:51820"),
-				Dst:    netip.MustParseAddrPort("5.6.7.8:51820"),
-			},
-		},
-		{
-			name: "server response",
-			ping: control.Ping{
-				PingTS: 1234567890,
-				SrcV4:  netip.MustParseAddrPort("5.6.7.8:51820"),
-				Dst:    netip.MustParseAddrPort("1.2.3.4:9999"),
-			},
-		},
-		{
-			name: "IPv6 only",
-			ping: control.Ping{
-				PingTS: 999,
-				SrcV6:  netip.MustParseAddrPort("[2001:db8::1]:51820"),
-				Dst:    netip.MustParseAddrPort("[2001:db8::2]:51820"),
-			},
-		},
-		{
-			name: "dual stack",
-			ping: control.Ping{
-				PingTS: 555,
-				SrcV4:  netip.MustParseAddrPort("1.2.3.4:51820"),
-				SrcV6:  netip.MustParseAddrPort("[2001:db8::1]:51820"),
-				Dst:    netip.MustParseAddrPort("5.6.7.8:9999"),
-			},
-		},
-		{
-			name: "no src known",
-			ping: control.Ping{
-				Dst: netip.MustParseAddrPort("5.6.7.8:51820"),
-			},
-		},
-	}
-
-	for _, tc := range cases {
-		t.Run(tc.name, func(t *testing.T) {
-			var buf [control.Size]byte
-			tc.ping.Marshal(buf[:])
-			got, err := control.Unmarshal(buf)
-			if err != nil {
-				t.Fatalf("Unmarshal: %v", err)
-			}
-			if got != tc.ping {
-				t.Fatalf("round-trip mismatch:\n  got  %+v\n  want %+v", got, tc.ping)
-			}
-		})
-	}
-}
-
-func TestUnmarshalBadVersion(t *testing.T) {
-	var buf [control.Size]byte
-	buf[0] = 99
-	if _, err := control.Unmarshal(buf); err == nil {
-		t.Fatal("expected error for unknown version, got nil")
-	}
-}
-
-func TestZeroEncoding(t *testing.T) {
-	var buf [control.Size]byte
-	(control.Ping{}).Marshal(buf[:])
-	for i, b := range buf {
-		if i == 0 {
-			continue // version byte
-		}
-		if b != 0 {
-			t.Fatalf("expected zero encoding at byte %d, got %d", i, b)
-		}
-	}
-}
-
-func TestRoleFor(t *testing.T) {
-	lo := netip.MustParseAddr("10.0.0.1")
-	hi := netip.MustParseAddr("10.0.0.2")
-
-	if control.RoleFor(lo, hi) != control.Client {
-		t.Error("lower IP should be client")
-	}
-	if control.RoleFor(hi, lo) != control.Server {
-		t.Error("higher IP should be server")
-	}
-}

peer/control/role.go

@@ -1,22 +0,0 @@
-package control
-
-import "net/netip"
-
-// Role identifies a peer's role in a ping exchange with a specific remote peer.
-type Role string
-
-const (
-	// Client initiates pings and measures RTT.
-	Client Role = "CLIENT"
-	// Server responds to pings.
-	Server Role = "SERVER"
-)
-
-// RoleFor returns the Role of local relative to remote.
-// The peer with the lower VPN IP is the client.
-func RoleFor(local, remote netip.Addr) Role {
-	if local.Compare(remote) < 0 {
-		return Client
-	}
-	return Server
-}

peer/control_conn.go

@@ -1,64 +0,0 @@
-package peer
-
-import (
-	"log"
-	"net"
-	"net/netip"
-
-	"vppn/peer/control"
-)
-
-var _ ControlConn = (*udpControlConn)(nil)
-
-type udpControlConn struct {
-	conn *net.UDPConn
-}
-
-// newUDPControlConn opens a UDP socket bound to localIP:port.
-func newUDPControlConn(localIP netip.Addr, port uint16) (*udpControlConn, error) {
-	addr := net.UDPAddrFromAddrPort(netip.AddrPortFrom(localIP, port))
-	conn, err := net.ListenUDP("udp4", addr)
-	if err != nil {
-		return nil, err
-	}
-	return &udpControlConn{conn: conn}, nil
-}
-
-func (c *udpControlConn) SendPing(dst netip.AddrPort, ping control.Ping, buf []byte) error {
-	_, err := c.conn.WriteToUDP(ping.Marshal(buf), net.UDPAddrFromAddrPort(dst))
-	return err
-}
-
-// run reads incoming ping packets and forwards them to ch until ctx is done.
-// Call this in a goroutine before starting the App event loop.
-func (c *udpControlConn) run(ch chan<- PingEvent) {
-	var buf [control.Size]byte
-	for {
-		n, src, err := c.conn.ReadFromUDP(buf[:])
-		if err != nil {
-			log.Printf("control read: %v", err)
-			continue
-		}
-
-		if n != control.Size {
-			continue
-		}
-
-		ping, err := control.Unmarshal(buf)
-		if err != nil {
-			log.Printf("control unmarshal: %v", err)
-			continue
-		}
-
-		srcIP, ok := netip.AddrFromSlice(src.IP)
-		if !ok {
-			continue
-		}
-
-		ch <- PingEvent{srcVPNIP: srcIP.Unmap(), ping: ping}
-	}
-}
-
-func (c *udpControlConn) Close() error {
-	return c.conn.Close()
-}

peer/controlmessage.go

@@ -0,0 +1,64 @@
+package peer
+
+import (
+	"net/netip"
+	"vppn/m"
+)
+
+// ----------------------------------------------------------------------------
+
+type controlMsg[T any] struct {
+	SrcIP   byte
+	SrcAddr netip.AddrPort
+	Packet  T
+}
+
+func parseControlMsg(srcIP byte, srcAddr netip.AddrPort, buf []byte) (any, error) {
+	switch buf[0] {
+
+	case packetTypeInit:
+		packet, err := parsePacketInit(buf)
+		return controlMsg[packetInit]{
+			SrcIP:   srcIP,
+			SrcAddr: srcAddr,
+			Packet:  packet,
+		}, err
+
+	case packetTypeSyn:
+		packet, err := parsePacketSyn(buf)
+		return controlMsg[packetSyn]{
+			SrcIP:   srcIP,
+			SrcAddr: srcAddr,
+			Packet:  packet,
+		}, err
+
+	case packetTypeAck:
+		packet, err := parsePacketAck(buf)
+		return controlMsg[packetAck]{
+			SrcIP:   srcIP,
+			SrcAddr: srcAddr,
+			Packet:  packet,
+		}, err
+
+	case packetTypeProbe:
+		packet, err := parsePacketProbe(buf)
+		return controlMsg[packetProbe]{
+			SrcIP:   srcIP,
+			SrcAddr: srcAddr,
+			Packet:  packet,
+		}, err
+
+	default:
+		return nil, errUnknownPacketType
+	}
+}
+
+// ----------------------------------------------------------------------------
+
+type peerUpdateMsg struct {
+	Peer *m.Peer
+}
+
+// ----------------------------------------------------------------------------
+
+type pingTimerMsg struct{}

peer/crypto.go

@@ -0,0 +1,30 @@
+package peer
+
+import (
+	"crypto/rand"
+	"log"
+
+	"golang.org/x/crypto/nacl/box"
+	"golang.org/x/crypto/nacl/sign"
+)
+
+type cryptoKeys struct {
+	PubKey      []byte
+	PrivKey     []byte
+	PubSignKey  []byte
+	PrivSignKey []byte
+}
+
+func generateKeys() cryptoKeys {
+	pubKey, privKey, err := box.GenerateKey(rand.Reader)
+	if err != nil {
+		log.Fatalf("Failed to generate encryption keys: %v", err)
+	}
+
+	pubSignKey, privSignKey, err := sign.GenerateKey(rand.Reader)
+	if err != nil {
+		log.Fatalf("Failed to generate signing keys: %v", err)
+	}
+
+	return cryptoKeys{pubKey[:], privKey[:], pubSignKey[:], privSignKey[:]}
+}

peer/device.go

@@ -1,79 +0,0 @@
-package peer
-
-import (
-	"errors"
-	"log"
-	"net/netip"
-	"syscall"
-	"time"
-
-	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
-)
-
-// devRetry calls fn up to 6 times with exponential backoff, retrying on EBUSY
-// (transient netlink contention during WireGuard handshake/rekey). Fatal on
-// any other error.
-func devRetry(vpnIP netip.Addr, op string, fn func() error) {
-	const attempts = 6
-	timeout := 10 * time.Millisecond
-	for i := range attempts {
-		err := fn()
-		if err == nil {
-			return
-		}
-		if errors.Is(err, syscall.EBUSY) && i < attempts-1 {
-			time.Sleep(timeout)
-			timeout *= 2
-			continue
-		}
-		log.Fatalf("%s %v: %v", op, vpnIP, err)
-	}
-}
-
-func (a *App) devPeers() []wgtypes.Peer {
-	peers, err := a.dev.Peers()
-	if err != nil {
-		log.Fatalf("Failed to get peers %v: %v", a.vpnIP, err)
-	}
-	return peers
-}
-
-func (a *App) devAddPeer(p *Peer) {
-	log.Printf("RELAYED: %s - %s ", p.Name, p.VPNIP.String())
-	devRetry(p.VPNIP, "AddPeer", func() error { return a.dev.AddPeer(p.PubKey()) })
-	p.State = StateRelayed
-}
-
-func (a *App) devAddDirect(p *Peer, endpoint netip.AddrPort) {
-	log.Printf("DIRECT: %s - %s @ %s", p.Name, p.VPNIP.String(), endpoint.String())
-	devRetry(p.VPNIP, "AddDirect", func() error { return a.dev.AddDirect(p.PubKey(), endpoint, p.VPNIP) })
-	p.State = StateDirect
-}
-
-func (a *App) devSetRelay(p *Peer, endpoint netip.AddrPort) {
-	log.Printf("RELAY: %s - %s @ %s", p.Name, p.VPNIP.String(), endpoint.String())
-	devRetry(p.VPNIP, "SetRelay", func() error { return a.dev.SetRelay(p.PubKey(), endpoint, a.vpnNet) })
-	p.State = StateDirect // Dirrect connection. The app marks peer as relay.
-}
-
-func (a *App) devPromote(p *Peer) {
-	ep := p.WGEndpoint()
-	if ep.IsValid() {
-		log.Printf("PROMOTED: %s - %s @ %s", p.Name, p.VPNIP.String(), p.WGEndpoint().String())
-	} else {
-		log.Printf("PROMOTED: %s - %s (no IP)", p.Name, p.VPNIP.String())
-	}
-	devRetry(p.VPNIP, "Promote", func() error { return a.dev.Promote(p.PubKey(), p.VPNIP) })
-	p.State = StateDirect
-}
-
-func (a *App) devAddProbe(p *Peer, endpoint netip.AddrPort) {
-	log.Printf("PROBE: %s - %s @ %s", p.Name, p.VPNIP.String(), endpoint.String())
-	devRetry(p.VPNIP, "AddProbe", func() error { return a.dev.AddProbe(p.PubKey(), endpoint) })
-	p.State = StateProbing
-}
-
-func (a *App) devRemove(p *Peer) {
-	log.Printf("REMOVED: %s - %s", p.Name, p.VPNIP.String())
-	devRetry(p.VPNIP, "RemovePeer", func() error { return a.dev.RemovePeer(p.PubKey()) })
-}

peer/dupcheck.go

@@ -0,0 +1,76 @@
+package peer
+
+type dupCheck struct {
+	bitSet
+	head        int
+	tail        int
+	headCounter uint64
+	tailCounter uint64 // Also next expected counter value.
+}
+
+func newDupCheck(headCounter uint64) *dupCheck {
+	return &dupCheck{
+		headCounter: headCounter,
+		tailCounter: headCounter + 1,
+		tail:        1,
+	}
+}
+
+func (dc *dupCheck) IsDup(counter uint64) bool {
+
+	// Before head => it's late, say it's a dup.
+	if counter < dc.headCounter {
+		return true
+	}
+
+	// It's within the counter bounds.
+	if counter < dc.tailCounter {
+		index := (int(counter-dc.headCounter) + dc.head) % bitSetSize
+		if dc.Get(index) {
+			return true
+		}
+
+		dc.Set(index)
+		return false
+	}
+
+	// It's more than 1 beyond the tail.
+	delta := counter - dc.tailCounter
+
+	// Full clear.
+	if delta >= bitSetSize-1 {
+		dc.ClearAll()
+		dc.Set(0)
+
+		dc.tail = 1
+		dc.head = 2
+		dc.tailCounter = counter + 1
+		dc.headCounter = dc.tailCounter - bitSetSize + 1
+
+		return false
+	}
+
+	// Clear if necessary.
+	for range delta {
+		dc.put(false)
+	}
+
+	dc.put(true)
+	return false
+}
+
+func (dc *dupCheck) put(set bool) {
+	if set {
+		dc.Set(dc.tail)
+	} else {
+		dc.Clear(dc.tail)
+	}
+
+	dc.tail = (dc.tail + 1) % bitSetSize
+	dc.tailCounter++
+
+	if dc.head == dc.tail {
+		dc.head = (dc.head + 1) % bitSetSize
+		dc.headCounter++
+	}
+}

peer/dupcheck_test.go

@@ -0,0 +1,57 @@
+package peer
+
+import (
+	"testing"
+)
+
+func TestDupCheck(t *testing.T) {
+	dc := newDupCheck(0)
+
+	for i := range bitSetSize {
+		if dc.IsDup(uint64(i)) {
+			t.Fatal("!")
+		}
+	}
+
+	type TestCase struct {
+		Counter uint64
+		Dup     bool
+	}
+
+	testCases := []TestCase{
+		{511, true},
+		{0, true},
+		{1, true},
+		{2, true},
+		{3, true},
+		{63, true},
+		{256, true},
+		{510, true},
+		{511, true},
+		{512, false},
+		{0, true},
+		{512, true},
+		{513, false},
+		{517, false},
+		{512, true},
+		{513, true},
+		{514, false},
+		{515, false},
+		{516, false},
+		{517, true},
+		{2512, false},
+		{2512, true},
+		{2001, true},
+		{2002, false},
+		{2002, true},
+		{4000, false},
+		{4000 - 511, true},  // Too old.
+		{4000 - 510, false}, // Just in the window.
+	}
+
+	for i, tc := range testCases {
+		if ok := dc.IsDup(tc.Counter); ok != tc.Dup {
+			t.Fatal(i, ok, tc)
+		}
+	}
+}

peer/errors.go

@@ -0,0 +1,8 @@
+package peer
+
+import "errors"
+
+var (
+	errMalformedPacket   = errors.New("malformed packet")
+	errUnknownPacketType = errors.New("unknown packet type")
+)

peer/fake_control_conn_test.go

@@ -1,43 +0,0 @@
-package peer
-
-import (
-	"net/netip"
-	"testing"
-
-	"vppn/peer/control"
-)
-
-type sentPing struct {
-	Dst  netip.AddrPort
-	Ping control.Ping
-}
-
-type fakeControlConn struct {
-	Sent []sentPing
-}
-
-func (f *fakeControlConn) SendPing(dst netip.AddrPort, ping control.Ping, _ []byte) error {
-	f.Sent = append(f.Sent, sentPing{Dst: dst, Ping: ping})
-	return nil
-}
-
-func (f *fakeControlConn) AssertNone(t *testing.T) {
-	t.Helper()
-	if len(f.Sent) != 0 {
-		t.Fatalf("expected no pings sent, got %d: %v", len(f.Sent), f.Sent)
-	}
-}
-
-func (f *fakeControlConn) AssertSent(t *testing.T, i int, dst netip.AddrPort, ping control.Ping) {
-	t.Helper()
-	if i >= len(f.Sent) {
-		t.Fatalf("no ping at index %d (have %d)", i, len(f.Sent))
-	}
-	got := f.Sent[i]
-	if got.Dst != dst {
-		t.Errorf("ping[%d].Dst = %v, want %v", i, got.Dst, dst)
-	}
-	if got.Ping != ping {
-		t.Errorf("ping[%d].Ping = %+v, want %+v", i, got.Ping, ping)
-	}
-}

peer/fake_wgdevice_test.go

@@ -1,123 +0,0 @@
-package peer
-
-import (
-	"net/netip"
-	"sync"
-	"testing"
-
-	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
-)
-
-// fakeWGDevice records every call made to it. It is safe to read Calls after
-// the event loop has processed the event under test (single-threaded loop
-// means no extra synchronisation needed, but the mutex guards concurrent test
-// helpers if needed).
-type fakeWGDevice struct {
-	mu    sync.Mutex
-	Calls []fakeCall
-	peers []wgtypes.Peer
-}
-
-type fakeCall struct {
-	Method   string
-	PubKey   wgtypes.Key
-	Endpoint netip.AddrPort
-	VPNiP    netip.Addr
-	Network  netip.Prefix
-}
-
-func (f *fakeWGDevice) record(c fakeCall) {
-	f.mu.Lock()
-	f.Calls = append(f.Calls, c)
-	f.mu.Unlock()
-}
-
-func (f *fakeWGDevice) Name() string { return "wg-test" }
-
-func (f *fakeWGDevice) Peers() ([]wgtypes.Peer, error) {
-	f.mu.Lock()
-	defer f.mu.Unlock()
-	out := make([]wgtypes.Peer, len(f.peers))
-	copy(out, f.peers)
-	return out, nil
-}
-
-func (f *fakeWGDevice) AddPeer(pubKey wgtypes.Key) error {
-	f.record(fakeCall{Method: "AddPeer", PubKey: pubKey})
-	return nil
-}
-
-func (f *fakeWGDevice) AddDirect(pubKey wgtypes.Key, endpoint netip.AddrPort, vpnIP netip.Addr) error {
-	f.record(fakeCall{Method: "AddDirect", PubKey: pubKey, Endpoint: endpoint, VPNiP: vpnIP})
-	return nil
-}
-
-func (f *fakeWGDevice) SetRelay(pubKey wgtypes.Key, endpoint netip.AddrPort, network netip.Prefix) error {
-	f.record(fakeCall{Method: "SetRelay", PubKey: pubKey, Endpoint: endpoint, Network: network})
-	return nil
-}
-
-func (f *fakeWGDevice) AddProbe(pubKey wgtypes.Key, endpoint netip.AddrPort) error {
-	f.record(fakeCall{Method: "AddProbe", PubKey: pubKey, Endpoint: endpoint})
-	return nil
-}
-
-func (f *fakeWGDevice) Promote(pubKey wgtypes.Key, vpnIP netip.Addr) error {
-	f.record(fakeCall{Method: "Promote", PubKey: pubKey, VPNiP: vpnIP})
-	return nil
-}
-
-func (f *fakeWGDevice) RemovePeer(pubKey wgtypes.Key) error {
-	f.record(fakeCall{Method: "RemovePeer", PubKey: pubKey})
-	return nil
-}
-
-// AssertNoCalls fails the test if any dev calls were recorded.
-func (f *fakeWGDevice) AssertNoCalls(t *testing.T) {
-	t.Helper()
-	f.mu.Lock()
-	defer f.mu.Unlock()
-	if len(f.Calls) != 0 {
-		t.Fatalf("unexpected dev calls: %v", f.Calls)
-	}
-}
-
-func (f *fakeWGDevice) AssertAddPeer(t *testing.T, i int, pubKey wgtypes.Key) {
-	t.Helper()
-	f.assertCall(t, i, fakeCall{Method: "AddPeer", PubKey: pubKey})
-}
-
-func (f *fakeWGDevice) AssertAddDirect(t *testing.T, i int, pubKey wgtypes.Key, endpoint netip.AddrPort, vpnIP netip.Addr) {
-	t.Helper()
-	f.assertCall(t, i, fakeCall{Method: "AddDirect", PubKey: pubKey, Endpoint: endpoint, VPNiP: vpnIP})
-}
-
-func (f *fakeWGDevice) AssertSetRelay(t *testing.T, i int, pubKey wgtypes.Key, endpoint netip.AddrPort, network netip.Prefix) {
-	t.Helper()
-	f.assertCall(t, i, fakeCall{Method: "SetRelay", PubKey: pubKey, Endpoint: endpoint, Network: network})
-}
-
-func (f *fakeWGDevice) AssertAddProbe(t *testing.T, i int, pubKey wgtypes.Key, endpoint netip.AddrPort) {
-	t.Helper()
-	f.assertCall(t, i, fakeCall{Method: "AddProbe", PubKey: pubKey, Endpoint: endpoint})
-}
-
-func (f *fakeWGDevice) AssertPromote(t *testing.T, i int, pubKey wgtypes.Key, vpnIP netip.Addr) {
-	t.Helper()
-	f.assertCall(t, i, fakeCall{Method: "Promote", PubKey: pubKey, VPNiP: vpnIP})
-}
-
-func (f *fakeWGDevice) AssertRemovePeer(t *testing.T, i int, pubKey wgtypes.Key) {
-	t.Helper()
-	f.assertCall(t, i, fakeCall{Method: "RemovePeer", PubKey: pubKey})
-}
-
-func (f *fakeWGDevice) assertCall(t *testing.T, i int, c fakeCall) {
-	t.Helper()
-	if len(f.Calls) <= i {
-		t.Fatalf("no call at index %d: %v", i, c)
-	}
-	if c != f.Calls[i] {
-		t.Fatalf("call[%d]: got %v, want %v", i, f.Calls[i], c)
-	}
-}

peer/files.go

@@ -0,0 +1,115 @@
+package peer
+
+import (
+	"encoding/json"
+	"log"
+	"os"
+	"path/filepath"
+	"vppn/m"
+)
+
+type LocalConfig struct {
+	LocalPeerIP byte
+	Network     []byte
+	PubKey      []byte
+	PrivKey     []byte
+	PubSignKey  []byte
+	PrivSignKey []byte
+}
+
+type startupCount struct {
+	Count uint16
+}
+
+func configDir(netName string) string {
+	d, err := os.UserHomeDir()
+	if err != nil {
+		log.Fatalf("Failed to get user home directory: %v", err)
+	}
+	return filepath.Join(d, ".vppn", netName)
+}
+
+func lockFilePath(netName string) string {
+	return filepath.Join(configDir(netName), "__lock__")
+}
+
+func peerConfigPath(netName string) string {
+	return filepath.Join(configDir(netName), "config.json")
+}
+
+func peerStatePath(netName string) string {
+	return filepath.Join(configDir(netName), "state.json")
+}
+
+func startupCountPath(netName string) string {
+	return filepath.Join(configDir(netName), "startup_count.json")
+}
+
+func statusSocketPath(netName string) string {
+	return filepath.Join(configDir(netName), "status.sock")
+}
+
+func storeJson(x any, outPath string) error {
+	outDir := filepath.Dir(outPath)
+	_ = os.MkdirAll(outDir, 0700)
+
+	tmpPath := outPath + ".tmp"
+	buf, err := json.Marshal(x)
+	if err != nil {
+		return err
+	}
+
+	f, err := os.Create(tmpPath)
+	if err != nil {
+		return err
+	}
+
+	if _, err := f.Write(buf); err != nil {
+		f.Close()
+		return err
+	}
+
+	if err := f.Sync(); err != nil {
+		f.Close()
+		return err
+	}
+
+	if err := f.Close(); err != nil {
+		return err
+	}
+
+	return os.Rename(tmpPath, outPath)
+}
+
+func storePeerConfig(netName string, pc LocalConfig) error {
+	return storeJson(pc, peerConfigPath(netName))
+}
+
+func storeNetworkState(netName string, ps m.NetworkState) error {
+	return storeJson(ps, peerStatePath(netName))
+}
+
+func loadJson(dataPath string, ptr any) error {
+	data, err := os.ReadFile(dataPath)
+	if err != nil {
+		return err
+	}
+
+	return json.Unmarshal(data, ptr)
+}
+
+func loadPeerConfig(netName string) (pc LocalConfig, err error) {
+	return pc, loadJson(peerConfigPath(netName), &pc)
+}
+
+func loadNetworkState(netName string) (ps m.NetworkState, err error) {
+	return ps, loadJson(peerStatePath(netName), &ps)
+}
+
+func loadStartupCount(netName string) (c startupCount, err error) {
+	return c, loadJson(startupCountPath(netName), &c)
+}
+
+func storeStartupCount(netName string, c startupCount) error {
+	return storeJson(c, startupCountPath(netName))
+}

peer/files_test.go

@@ -0,0 +1,57 @@
+package peer
+
+import (
+	"path/filepath"
+	"reflect"
+	"testing"
+)
+
+func TestFilePaths(t *testing.T) {
+	confDir := configDir("netName")
+	if filepath.Base(confDir) != "netName" {
+		t.Fatal(confDir)
+	}
+	if filepath.Base(filepath.Dir(confDir)) != ".vppn" {
+		t.Fatal(confDir)
+	}
+
+	path := peerConfigPath("netName")
+	if path != filepath.Join(confDir, "config.json") {
+		t.Fatal(path)
+	}
+
+	path = peerStatePath("netName")
+	if path != filepath.Join(confDir, "state.json") {
+		t.Fatal(path)
+	}
+}
+
+func TestStoreLoadJson(t *testing.T) {
+	type Object struct {
+		Name  string
+		Age   int
+		Price float64
+	}
+
+	tmpDir := t.TempDir()
+	outPath := filepath.Join(tmpDir, "object.json")
+
+	obj := Object{
+		Name:  "Jason",
+		Age:   22,
+		Price: 123.534,
+	}
+
+	if err := storeJson(obj, outPath); err != nil {
+		t.Fatal(err)
+	}
+
+	obj2 := Object{}
+	if err := loadJson(outPath, &obj2); err != nil {
+		t.Fatal(err)
+	}
+
+	if !reflect.DeepEqual(obj, obj2) {
+		t.Fatal(obj, obj2)
+	}
+}

peer/globals.go

@@ -0,0 +1,109 @@
+package peer
+
+import (
+	"io"
+	"net"
+	"net/netip"
+	"sync"
+	"sync/atomic"
+	"time"
+)
+
+const (
+	version = 1
+
+	bufferSize = 8192 // Enough for data packets and encryption buffers.
+
+	if_mtu       = 1200
+	if_queue_len = 2048
+
+	controlCipherOverhead = 16
+	dataCipherOverhead    = 16
+	signingOverhead       = 64
+
+	pingInterval                  = 8 * time.Second
+	timeoutInterval               = 30 * time.Second
+	broadcastInterval             = 16 * time.Second
+	broadcastErrorTimeoutInterval = 8 * time.Second
+)
+
+var multicastAddr = net.UDPAddrFromAddrPort(netip.AddrPortFrom(
+	netip.AddrFrom4([4]byte{224, 0, 0, 157}),
+	4560))
+
+// ----------------------------------------------------------------------------
+
+type Globals struct {
+	LocalConfig // Embed, immutable.
+
+	// The number of startups
+	StartupCount uint16
+
+	// Local public address (if available). Immutable.
+	LocalAddr netip.AddrPort
+
+	// True if local public address is valid. Immutable.
+	LocalAddrValid bool
+
+	// All remote peers by VPN IP.
+	RemotePeers [256]*atomic.Pointer[Remote]
+
+	// Discovered public addresses.
+	PubAddrs *pubAddrStore
+
+	// Attempts to ensure that we have a relay available.
+	RelayHandler *relayHandler
+
+	// Send UDP - Global function to write UDP packets.
+	SendUDP func(b []byte, addr netip.AddrPort) (n int, err error)
+
+	// Global TUN interface.
+	IFace io.ReadWriteCloser
+
+	// For trace ID.
+	NewTraceID func() uint64
+}
+
+func NewGlobals(
+	localConfig LocalConfig,
+	startupCount startupCount,
+	localAddr netip.AddrPort,
+	conn *net.UDPConn,
+	iface io.ReadWriteCloser,
+) (g Globals) {
+	g.LocalConfig = localConfig
+	g.StartupCount = startupCount.Count
+
+	g.LocalAddr = localAddr
+	g.LocalAddrValid = localAddr.IsValid()
+
+	g.PubAddrs = newPubAddrStore(localAddr)
+
+	g.RelayHandler = newRelayHandler()
+
+	// Use a lock here avoids starvation, at least on my Linux machine.
+	sendLock := sync.Mutex{}
+	g.SendUDP = func(b []byte, addr netip.AddrPort) (int, error) {
+		sendLock.Lock()
+		n, err := conn.WriteToUDPAddrPort(b, addr)
+		sendLock.Unlock()
+		return n, err
+	}
+
+	g.IFace = iface
+
+	traceID := (uint64(g.StartupCount) << 48) + 1
+	g.NewTraceID = func() uint64 {
+		return atomic.AddUint64(&traceID, 1)
+	}
+
+	for i := range g.RemotePeers {
+		g.RemotePeers[i] = &atomic.Pointer[Remote]{}
+	}
+
+	for i := range g.RemotePeers {
+		g.RemotePeers[i].Store(newRemote(g, byte(i)))
+	}
+
+	return g
+}

peer/header.go

@@ -0,0 +1,47 @@
+package peer
+
+import "unsafe"
+
+// ----------------------------------------------------------------------------
+
+const (
+	headerSize        = 12
+	controlHeaderSize = 24
+	dataHeaderSize    = 12
+
+	dataStreamID    = 1
+	controlStreamID = 2
+)
+
+type Header struct {
+	Version  byte
+	StreamID byte
+	SourceIP byte
+	DestIP   byte
+	Counter  uint64 // Init with time.Now().Unix << 30 to ensure monotonic.
+}
+
+func parseHeader(b []byte) (h Header) {
+	h.Version = b[0]
+	h.StreamID = b[1]
+	h.SourceIP = b[2]
+	h.DestIP = b[3]
+	h.Counter = *(*uint64)(unsafe.Pointer(&b[4]))
+	return h
+}
+
+func (h *Header) Parse(b []byte) {
+	h.Version = b[0]
+	h.StreamID = b[1]
+	h.SourceIP = b[2]
+	h.DestIP = b[3]
+	h.Counter = *(*uint64)(unsafe.Pointer(&b[4]))
+}
+
+func (h *Header) Marshal(buf []byte) {
+	buf[0] = h.Version
+	buf[1] = h.StreamID
+	buf[2] = h.SourceIP
+	buf[3] = h.DestIP
+	*(*uint64)(unsafe.Pointer(&buf[4])) = h.Counter
+}

peer/header_test.go

@@ -0,0 +1,21 @@
+package peer
+
+import "testing"
+
+func TestHeaderMarshalParse(t *testing.T) {
+	nIn := Header{
+		StreamID: 23,
+		Counter:  3212,
+		SourceIP: 34,
+		DestIP:   200,
+	}
+
+	buf := make([]byte, headerSize)
+	nIn.Marshal(buf)
+
+	nOut := Header{}
+	nOut.Parse(buf)
+	if nIn != nOut {
+		t.Fatal(nIn, nOut)
+	}
+}

peer/hosts.go

@@ -1,128 +0,0 @@
-package peer
-
-import (
-	"fmt"
-	"log"
-	"net/netip"
-	"os"
-	"sort"
-	"strings"
-	"syscall"
-
-	"git.crumpington.com/lib/go/flock"
-)
-
-const (
-	hostsFile  = "/etc/hosts"
-	hostsBegin = "# BEGIN vppn"
-	hostsEnd   = "# END vppn"
-)
-
-// hostMarkers returns the begin/end marker lines that delimit the managed
-// section for localDomain. The domain is wrapped in parentheses so one domain's
-// marker can never be a prefix of another's (e.g. "net" vs "net2") when
-// multiple vppn instances share /etc/hosts.
-func hostMarkers(localDomain string) (begin, end string) {
-	return hostsBegin + "(" + localDomain + ")", hostsEnd + "(" + localDomain + ")"
-}
-
-// updateHosts rewrites the managed vppn section in /etc/hosts using the
-// current peersByIP map. Peers without a Name are skipped.
-func (a *App) updateHosts() {
-	if a.localDomain == "" {
-		return
-	}
-	if err := updateHosts(hostsFile, a.localDomain, a.peersByIP); err != nil {
-		log.Printf("Failed to update hosts file: %v", err)
-	}
-}
-
-func updateHosts(hostsPath, localDomain string, peers map[netip.Addr]*Peer) error {
-	lockFile, err := flock.Lock(hostsPath + ".vppn.lock")
-	if err != nil {
-		return err
-	}
-	defer lockFile.Close()
-
-	begin, end := hostMarkers(localDomain)
-
-	info, err := os.Stat(hostsPath)
-	if err != nil {
-		return err
-	}
-
-	raw, err := os.ReadFile(hostsPath)
-	if err != nil {
-		return err
-	}
-
-	data := string(raw)
-
-	before := strings.TrimSpace(data)
-	after := ""
-
-	if idxBegin := strings.Index(data, begin); idxBegin != -1 {
-		idxEnd := strings.Index(data[idxBegin:], end)
-		if idxEnd != -1 {
-			after = strings.TrimSpace(data[idxBegin+idxEnd+len(end):])
-		}
-		before = strings.TrimSpace(data[:idxBegin])
-	}
-
-	b := strings.Builder{}
-	b.WriteString(before)
-	b.WriteRune('\n')
-	b.WriteString(after)
-	b.WriteRune('\n')
-	b.WriteRune('\n')
-
-	b.WriteString(begin)
-	b.WriteRune('\n')
-
-	// Collect entries so we can sort by IP for stable output. Pad the IP
-	// column to the width of the widest possible address ("255.255.255.255")
-	// for readability.
-	type entry struct {
-		ip   netip.Addr
-		host string
-	}
-	var entries []entry
-	for ip, p := range peers {
-		if p.Name == "" {
-			continue
-		}
-		entries = append(entries, entry{ip: ip, host: p.Name + "." + localDomain})
-	}
-	sort.Slice(entries, func(i, j int) bool {
-		return entries[i].ip.Less(entries[j].ip)
-	})
-
-	for _, e := range entries {
-		b.WriteString(fmt.Sprintf("%-15s %s\n", e.ip.String(), e.host))
-	}
-
-	b.WriteString(end)
-	b.WriteRune('\n')
-
-	// Write to a temp file in the same directory, then rename over the
-	// original so readers never observe a partial file. Preserve the
-	// original's mode and ownership, since rename replaces the inode.
-	tmpPath := hostsPath + ".vppn.tmp"
-	if err := os.WriteFile(tmpPath, []byte(b.String()), info.Mode().Perm()); err != nil {
-		return err
-	}
-
-	if st, ok := info.Sys().(*syscall.Stat_t); ok {
-		if err := os.Chown(tmpPath, int(st.Uid), int(st.Gid)); err != nil {
-			os.Remove(tmpPath)
-			return err
-		}
-	}
-
-	if err := os.Rename(tmpPath, hostsPath); err != nil {
-		os.Remove(tmpPath)
-		return err
-	}
-
-	return nil
-}

peer/hosts_test.go

@@ -1,205 +0,0 @@
-package peer
-
-import (
-	"net/netip"
-	"os"
-	"path/filepath"
-	"sort"
-	"strings"
-	"testing"
-)
-
-// writeTempHosts creates a temp hosts file with the given content and returns
-// its path.
-func writeTempHosts(t *testing.T, content string) string {
-	t.Helper()
-	path := filepath.Join(t.TempDir(), "hosts")
-	if err := os.WriteFile(path, []byte(content), 0600); err != nil {
-		t.Fatal(err)
-	}
-	return path
-}
-
-// readManagedSection returns the lines between the begin/end markers for the
-// given localDomain, plus everything outside the section ("outside").
-func readManagedSection(t *testing.T, path, localDomain string) (inside, outside []string) {
-	t.Helper()
-	raw, err := os.ReadFile(path)
-	if err != nil {
-		t.Fatal(err)
-	}
-	begin, end := hostMarkers(localDomain)
-
-	inSection := false
-	for _, line := range strings.Split(string(raw), "\n") {
-		switch {
-		case strings.HasPrefix(line, begin):
-			inSection = true
-		case strings.HasPrefix(line, end):
-			inSection = false
-		case inSection:
-			if f := strings.Join(strings.Fields(line), " "); f != "" {
-				inside = append(inside, f)
-			}
-		default:
-			if f := strings.Join(strings.Fields(line), " "); f != "" {
-				outside = append(outside, f)
-			}
-		}
-	}
-	return inside, outside
-}
-
-func peer(name string) *Peer {
-	return &Peer{Name: name}
-}
-
-func TestUpdateHosts_AddsSection(t *testing.T) {
-	path := writeTempHosts(t, "127.0.0.1 localhost\n")
-
-	peers := map[netip.Addr]*Peer{
-		netip.MustParseAddr("10.11.12.1"):  peer("hub"),
-		netip.MustParseAddr("10.11.12.10"): peer("laptop"),
-	}
-
-	if err := updateHosts(path, "mynet.local", peers); err != nil {
-		t.Fatal(err)
-	}
-
-	inside, outside := readManagedSection(t, path, "mynet.local")
-
-	sort.Strings(inside)
-	want := []string{
-		"10.11.12.1 hub.mynet.local",
-		"10.11.12.10 laptop.mynet.local",
-	}
-	if strings.Join(inside, "\n") != strings.Join(want, "\n") {
-		t.Errorf("managed section = %v, want %v", inside, want)
-	}
-
-	if !contains(outside, "127.0.0.1 localhost") {
-		t.Errorf("original content lost; outside = %v", outside)
-	}
-}
-
-func TestUpdateHosts_ReplacesExistingSection(t *testing.T) {
-	path := writeTempHosts(t, "127.0.0.1 localhost\n")
-
-	// First write.
-	first := map[netip.Addr]*Peer{
-		netip.MustParseAddr("10.11.12.1"): peer("hub"),
-	}
-	if err := updateHosts(path, "mynet.local", first); err != nil {
-		t.Fatal(err)
-	}
-
-	// Second write with a different set of peers.
-	second := map[netip.Addr]*Peer{
-		netip.MustParseAddr("10.11.12.20"): peer("phone"),
-	}
-	if err := updateHosts(path, "mynet.local", second); err != nil {
-		t.Fatal(err)
-	}
-
-	inside, outside := readManagedSection(t, path, "mynet.local")
-
-	if len(inside) != 1 || inside[0] != "10.11.12.20 phone.mynet.local" {
-		t.Errorf("section not replaced; inside = %v", inside)
-	}
-	if contains(inside, "10.11.12.1 hub.mynet.local") {
-		t.Errorf("stale entry remained; inside = %v", inside)
-	}
-	if !contains(outside, "127.0.0.1 localhost") {
-		t.Errorf("original content lost; outside = %v", outside)
-	}
-}
-
-func TestUpdateHosts_SkipsEmptyNames(t *testing.T) {
-	path := writeTempHosts(t, "127.0.0.1 localhost\n")
-
-	peers := map[netip.Addr]*Peer{
-		netip.MustParseAddr("10.11.12.1"):  peer("hub"),
-		netip.MustParseAddr("10.11.12.99"): peer(""), // no name
-	}
-	if err := updateHosts(path, "mynet.local", peers); err != nil {
-		t.Fatal(err)
-	}
-
-	inside, _ := readManagedSection(t, path, "mynet.local")
-	if len(inside) != 1 || inside[0] != "10.11.12.1 hub.mynet.local" {
-		t.Errorf("expected only named peer; inside = %v", inside)
-	}
-}
-
-func TestUpdateHosts_Idempotent(t *testing.T) {
-	path := writeTempHosts(t, "127.0.0.1 localhost\n")
-
-	peers := map[netip.Addr]*Peer{
-		netip.MustParseAddr("10.11.12.1"): peer("hub"),
-	}
-	if err := updateHosts(path, "mynet.local", peers); err != nil {
-		t.Fatal(err)
-	}
-	first, err := os.ReadFile(path)
-	if err != nil {
-		t.Fatal(err)
-	}
-	if err := updateHosts(path, "mynet.local", peers); err != nil {
-		t.Fatal(err)
-	}
-	second, err := os.ReadFile(path)
-	if err != nil {
-		t.Fatal(err)
-	}
-	if string(first) != string(second) {
-		t.Errorf("repeated update changed file:\nfirst:\n%s\nsecond:\n%s", first, second)
-	}
-}
-
-// TestUpdateHosts_PrefixDomainsCoexist guards finding 4.4: two domains where
-// one label is a prefix of the other ("net" vs "net2") must each manage their
-// own section without clobbering the other's, even sharing one hosts file.
-func TestUpdateHosts_PrefixDomainsCoexist(t *testing.T) {
-	path := writeTempHosts(t, "127.0.0.1 localhost\n")
-
-	if err := updateHosts(path, "net2.local", map[netip.Addr]*Peer{
-		netip.MustParseAddr("10.0.2.1"): peer("a"),
-	}); err != nil {
-		t.Fatal(err)
-	}
-	if err := updateHosts(path, "net.local", map[netip.Addr]*Peer{
-		netip.MustParseAddr("10.0.1.1"): peer("b"),
-	}); err != nil {
-		t.Fatal(err)
-	}
-
-	// Both sections coexist after writing the prefix domain.
-	if in, _ := readManagedSection(t, path, "net2.local"); len(in) != 1 || in[0] != "10.0.2.1 a.net2.local" {
-		t.Errorf("net2 section clobbered: %v", in)
-	}
-	if in, _ := readManagedSection(t, path, "net.local"); len(in) != 1 || in[0] != "10.0.1.1 b.net.local" {
-		t.Errorf("net section wrong: %v", in)
-	}
-
-	// Re-updating net2 must not disturb the net section.
-	if err := updateHosts(path, "net2.local", map[netip.Addr]*Peer{
-		netip.MustParseAddr("10.0.2.2"): peer("c"),
-	}); err != nil {
-		t.Fatal(err)
-	}
-	if in, _ := readManagedSection(t, path, "net.local"); len(in) != 1 || in[0] != "10.0.1.1 b.net.local" {
-		t.Errorf("net section disturbed by net2 update: %v", in)
-	}
-	if in, _ := readManagedSection(t, path, "net2.local"); len(in) != 1 || in[0] != "10.0.2.2 c.net2.local" {
-		t.Errorf("net2 section not updated: %v", in)
-	}
-}
-
-func contains(ss []string, s string) bool {
-	for _, x := range ss {
-		if x == s {
-			return true
-		}
-	}
-	return false
-}

peer/hub_poller.go

@@ -1,153 +0,0 @@
-package peer
-
-import (
-	"encoding/json"
-	"io"
-	"log"
-	"net/http"
-	"net/netip"
-	"net/url"
-	"time"
-
-	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
-
-	"vppn/m"
-)
-
-const hubPollInterval = 64 * time.Second
-
-type HubPoller struct {
-	selfVPNIP netip.Addr
-	vpnNet    netip.Prefix
-	hubURL    string
-	apiKey    string
-	statePath string // where the network state cache is persisted
-	addCh     chan<- m.Peer
-	removeCh  chan<- wgtypes.Key
-	known     map[wgtypes.Key]struct{} // pubKeys currently configured
-}
-
-func NewHubPoller(
-	selfVPNIP netip.Addr,
-	vpnNet netip.Prefix,
-	hubURL, apiKey string,
-	statePath string,
-	addCh chan<- m.Peer,
-	removeCh chan<- wgtypes.Key,
-) (*HubPoller, error) {
-	u, err := url.Parse(hubURL)
-	if err != nil {
-		return nil, err
-	}
-	u.Path = "/peer/fetch-state/"
-
-	return &HubPoller{
-		selfVPNIP: selfVPNIP,
-		vpnNet:    vpnNet,
-		hubURL:    u.String(),
-		apiKey:    apiKey,
-		statePath: statePath,
-		addCh:     addCh,
-		removeCh:  removeCh,
-		known:     make(map[wgtypes.Key]struct{}),
-	}, nil
-}
-
-func (hp *HubPoller) Run() {
-	// Prime from the on-disk cache before reaching the hub, so the peer
-	// configures WireGuard from its last known state even if the hub is down.
-	// known starts empty, so this emits every cached peer as an add; the first
-	// real poll then emits only deltas (adds for new peers, removes for gone).
-	if state, err := loadNetworkState(hp.statePath); err == nil {
-		hp.apply(state)
-	}
-
-	hp.poll()
-	for range time.Tick(hubPollInterval) {
-		hp.poll()
-	}
-}
-
-func (hp *HubPoller) poll() {
-	req, err := http.NewRequest(http.MethodGet, hp.hubURL, nil)
-	if err != nil {
-		log.Printf("[HubPoller] build request: %v", err)
-		return
-	}
-	req.SetBasicAuth("", hp.apiKey)
-
-	client := &http.Client{Timeout: 32 * time.Second}
-	resp, err := client.Do(req)
-	if err != nil {
-		log.Printf("[HubPoller] fetch: %v", err)
-		return
-	}
-	defer resp.Body.Close()
-
-	if resp.StatusCode != http.StatusOK {
-		log.Printf("[HubPoller] unexpected status %d", resp.StatusCode)
-		return
-	}
-
-	body, err := io.ReadAll(resp.Body)
-	if err != nil {
-		log.Printf("[HubPoller] read body: %v", err)
-		return
-	}
-
-	var state m.NetworkState
-	if err := json.Unmarshal(body, &state); err != nil {
-		log.Printf("[HubPoller] unmarshal: %v", err)
-		return
-	}
-
-	// Persist only when the state actually changed, to avoid needless writes
-	// on every poll.
-	if hp.apply(state) {
-		if err := saveNetworkState(hp.statePath, state); err != nil {
-			log.Printf("[HubPoller] save state: %v", err)
-		}
-	}
-}
-
-// apply diffs state against the set of known peers, emitting an add for each
-// newly-seen peer and a remove for each that disappeared. It returns true if
-// anything changed. A peer's config is immutable under a stable WG key (the hub
-// has no peer-edit path), so a key already in known needs no re-emit.
-func (hp *HubPoller) apply(state m.NetworkState) (changed bool) {
-	seen := make(map[wgtypes.Key]struct{}, len(hp.known))
-
-	netAddr := hp.vpnNet.Addr().As4()
-
-	for _, p := range state.Peers {
-		if p.WGPubKey == (wgtypes.Key{}) {
-			continue
-		}
-
-		octets := netAddr
-		octets[3] = p.PeerIP
-		vpnIP := netip.AddrFrom4(octets)
-		if vpnIP == hp.selfVPNIP {
-			continue
-		}
-
-		seen[p.WGPubKey] = struct{}{}
-
-		if _, ok := hp.known[p.WGPubKey]; ok {
-			continue
-		}
-		hp.known[p.WGPubKey] = struct{}{}
-		hp.addCh <- p
-		changed = true
-	}
-
-	for key := range hp.known {
-		if _, ok := seen[key]; !ok {
-			delete(hp.known, key)
-			hp.removeCh <- key
-			changed = true
-		}
-	}
-
-	return changed
-}

peer/hub_poller_test.go

@@ -1,80 +0,0 @@
-package peer
-
-import (
-	"net/netip"
-	"testing"
-
-	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
-
-	"vppn/m"
-)
-
-func testPoller(t *testing.T) (*HubPoller, chan m.Peer, chan wgtypes.Key) {
-	t.Helper()
-	addCh := make(chan m.Peer, 8)
-	removeCh := make(chan wgtypes.Key, 8)
-	hp := &HubPoller{
-		selfVPNIP: netip.MustParseAddr("10.0.0.1"),
-		vpnNet:    netip.MustParsePrefix("10.0.0.0/24"),
-		addCh:     addCh,
-		removeCh:  removeCh,
-		known:     make(map[wgtypes.Key]struct{}),
-	}
-	return hp, addCh, removeCh
-}
-
-func stateWith(key wgtypes.Key, peerIP byte) m.NetworkState {
-	return m.NetworkState{Peers: []m.Peer{{
-		PeerIP:   peerIP,
-		WGPubKey: key,
-	}}}
-}
-
-func TestApply_EmitsAddsAndReportsChange(t *testing.T) {
-	hp, addCh, _ := testPoller(t)
-	key := mustKey(t)
-
-	if changed := hp.apply(stateWith(key, 2)); !changed {
-		t.Fatal("expected changed=true on first apply")
-	}
-	if len(addCh) != 1 {
-		t.Fatalf("expected 1 add, got %d", len(addCh))
-	}
-	if got := <-addCh; got.WGPubKey != key {
-		t.Errorf("add pubkey mismatch")
-	}
-}
-
-func TestApply_NoChangeWhenKnown(t *testing.T) {
-	hp, addCh, _ := testPoller(t)
-	key := mustKey(t)
-
-	hp.apply(stateWith(key, 2))
-	<-addCh // drain initial add
-
-	if changed := hp.apply(stateWith(key, 2)); changed {
-		t.Fatal("expected changed=false when peer already known")
-	}
-	if len(addCh) != 0 {
-		t.Fatalf("expected no re-emit, got %d adds", len(addCh))
-	}
-}
-
-func TestApply_RemovesVanishedPeer(t *testing.T) {
-	hp, addCh, removeCh := testPoller(t)
-	key := mustKey(t)
-
-	hp.apply(stateWith(key, 2))
-	<-addCh
-
-	// Empty state: the peer is gone.
-	if changed := hp.apply(m.NetworkState{}); !changed {
-		t.Fatal("expected changed=true when peer vanishes")
-	}
-	if len(removeCh) != 1 {
-		t.Fatalf("expected 1 remove, got %d", len(removeCh))
-	}
-	if got := <-removeCh; got != key {
-		t.Errorf("remove key mismatch")
-	}
-}

peer/hubpoller.go

@@ -0,0 +1,111 @@
+package peer
+
+import (
+	"encoding/json"
+	"io"
+	"log"
+	"net/http"
+	"net/url"
+	"time"
+	"vppn/m"
+)
+
+type HubPoller struct {
+	Globals
+	client   *http.Client
+	req      *http.Request
+	versions [256]int64
+	netName  string
+}
+
+func NewHubPoller(
+	g Globals,
+	netName,
+	hubURL,
+	apiKey string,
+) (*HubPoller, error) {
+	u, err := url.Parse(hubURL)
+	if err != nil {
+		return nil, err
+	}
+	u.Path = "/peer/fetch-state/"
+
+	client := &http.Client{Timeout: 8 * time.Second}
+
+	req := &http.Request{
+		Method: http.MethodGet,
+		URL:    u,
+		Header: http.Header{},
+	}
+	req.SetBasicAuth("", apiKey)
+
+	return &HubPoller{
+		Globals: g,
+		client:  client,
+		req:     req,
+		netName: netName,
+	}, nil
+}
+
+func (hp *HubPoller) logf(s string, args ...any) {
+	log.Printf("[HubPoller] "+s, args...)
+}
+
+func (hp *HubPoller) Run() {
+	state, err := loadNetworkState(hp.netName)
+	if err != nil {
+		hp.logf("Failed to load network state: %v", err)
+		hp.logf("Polling hub...")
+		hp.pollHub()
+	} else {
+		hp.applyNetworkState(state)
+	}
+
+	for range time.Tick(64 * time.Second) {
+		hp.pollHub()
+	}
+}
+
+func (hp *HubPoller) pollHub() {
+	var state m.NetworkState
+
+	resp, err := hp.client.Do(hp.req)
+	if err != nil {
+		hp.logf("Failed to fetch peer state: %v", err)
+		return
+	}
+	body, err := io.ReadAll(resp.Body)
+	_ = resp.Body.Close()
+	if err != nil {
+		hp.logf("Failed to read body from hub: %v", err)
+		return
+	}
+
+	if err := json.Unmarshal(body, &state); err != nil {
+		hp.logf("Failed to unmarshal response from hub: %v\n%s", err, body)
+		return
+	}
+
+	if err := storeNetworkState(hp.netName, state); err != nil {
+		hp.logf("Failed to store network state: %v", err)
+	}
+
+	hp.applyNetworkState(state)
+}
+
+func (hp *HubPoller) applyNetworkState(state m.NetworkState) {
+	for i, peer := range state.Peers {
+		if i == int(hp.LocalPeerIP) {
+			continue
+		}
+
+		if peer != nil && peer.Version == hp.versions[i] {
+			continue
+		}
+
+		hp.RemotePeers[i].Load().HandlePeerUpdate(peerUpdateMsg{Peer: state.Peers[i]})
+		if peer != nil {
+			hp.versions[i] = peer.Version
+		}
+	}
+}

peer/ifreader.go

@@ -0,0 +1,73 @@
+package peer
+
+import (
+	"log"
+)
+
+type IFReader struct {
+	Globals
+}
+
+func NewIFReader(g Globals) *IFReader {
+	return &IFReader{Globals: g}
+}
+
+func (r *IFReader) Run() {
+	packet := make([]byte, bufferSize)
+	for {
+		r.handleNextPacket(packet)
+	}
+}
+
+func (r *IFReader) handleNextPacket(packet []byte) {
+	packet = r.readNextPacket(packet)
+	remoteIP, ok := r.parsePacket(packet)
+	if !ok {
+		return
+	}
+	r.RemotePeers[remoteIP].Load().SendDataTo(packet)
+}
+
+func (r *IFReader) readNextPacket(buf []byte) []byte {
+	n, err := r.IFace.Read(buf[:cap(buf)])
+	if err != nil {
+		log.Fatalf("Failed to read from interface: %v", err)
+	}
+
+	return buf[:n]
+}
+
+// parsePacket returns the VPN ip for the packet, and a boolean indicating
+// success.
+func (r *IFReader) parsePacket(buf []byte) (byte, bool) {
+	n := len(buf)
+	if n == 0 {
+		return 0, false
+	}
+
+	version := buf[0] >> 4
+
+	switch version {
+	case 4:
+		if n < 20 {
+			r.logf("Short IPv4 packet: %d", len(buf))
+			return 0, false
+		}
+		return buf[19], true
+
+	case 6:
+		if len(buf) < 40 {
+			r.logf("Short IPv6 packet: %d", len(buf))
+			return 0, false
+		}
+		return buf[39], true
+
+	default:
+		r.logf("Invalid IP packet version: %v", version)
+		return 0, false
+	}
+}
+
+func (*IFReader) logf(s string, args ...any) {
+	log.Printf("[IFReader] "+s, args...)
+}

peer/ifreader_test.go

@@ -0,0 +1,81 @@
+package peer
+
+/*
+func TestIFReader_IPv4(t *testing.T) {
+	p1, p2, _ := NewPeersForTesting()
+
+	pkt := make([]byte, 1234)
+	pkt[0] = 4 << 4
+	pkt[19] = 2 // IP.
+
+	p1.IFace.UserWrite(pkt)
+	p1.IFReader.handleNextPacket(newBuf())
+
+	packets := p2.Conn.Packets()
+	if len(packets) != 1 {
+		t.Fatal(packets)
+	}
+}
+
+func TestIFReader_IPv6(t *testing.T) {
+	p1, p2, _ := NewPeersForTesting()
+
+	pkt := make([]byte, 1234)
+	pkt[0] = 6 << 4
+	pkt[39] = 2 // IP.
+
+	p1.IFace.UserWrite(pkt)
+	p1.IFReader.handleNextPacket(newBuf())
+
+	packets := p2.Conn.Packets()
+	if len(packets) != 1 {
+		t.Fatal(packets)
+	}
+}
+
+func TestIFReader_parsePacket_emptyPacket(t *testing.T) {
+	r := NewIFReader(nil, nil)
+	pkt := make([]byte, 0)
+	if ip, ok := r.parsePacket(pkt); ok {
+		t.Fatal(ip, ok)
+	}
+}
+
+func TestIFReader_parsePacket_invalidIPVersion(t *testing.T) {
+	r := NewIFReader(nil, nil)
+
+	for i := byte(1); i < 16; i++ {
+		if i == 4 || i == 6 {
+			continue
+		}
+		pkt := make([]byte, 1234)
+		pkt[0] = i << 4
+
+		if ip, ok := r.parsePacket(pkt); ok {
+			t.Fatal(i, ip, ok)
+		}
+	}
+}
+
+func TestIFReader_parsePacket_shortIPv4(t *testing.T) {
+	r := NewIFReader(nil, nil)
+
+	pkt := make([]byte, 19)
+	pkt[0] = 4 << 4
+
+	if ip, ok := r.parsePacket(pkt); ok {
+		t.Fatal(ip, ok)
+	}
+}
+
+func TestIFReader_parsePacket_shortIPv6(t *testing.T) {
+	r := NewIFReader(nil, nil)
+
+	pkt := make([]byte, 39)
+	pkt[0] = 6 << 4
+
+	if ip, ok := r.parsePacket(pkt); ok {
+		t.Fatal(ip, ok)
+	}
+}
+*/

peer/init.go

@@ -1,190 +0,0 @@
-package peer
-
-import (
-	"bytes"
-	"crypto/rand"
-	"encoding/base64"
-	"encoding/json"
-	"fmt"
-	"net/http"
-	"net/netip"
-	"os"
-
-	"golang.org/x/crypto/nacl/sign"
-	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
-
-	"vppn/m"
-)
-
-// LocalState is the persisted identity for this peer, written on first run and
-// loaded on every subsequent run.
-type LocalState struct {
-	PrivKey     wgtypes.Key
-	SignKey     [64]byte // nacl/sign Ed25519 private key
-	VPNIP       netip.Addr
-	VPNNet      netip.Prefix
-	WGPort      uint16
-	IsRelay     bool
-	IsPublic    bool
-	LocalDomain string
-}
-
-// localStateJSON is the on-disk representation.
-type localStateJSON struct {
-	PrivKey     string
-	SignKey     string
-	VPNIP       netip.Addr
-	VPNNet      netip.Prefix
-	WGPort      uint16
-	IsRelay     bool
-	IsPublic    bool
-	LocalDomain string
-}
-
-// LoadOrInit loads LocalState from path, or registers with the hub and creates
-// the file if it doesn't exist.
-func LoadOrInit(statePath, hubURL, apiKey string) (LocalState, error) {
-	var state LocalState
-	switch err := loadJSON(statePath, &state); {
-	case err == nil:
-		return state, nil
-	case !os.IsNotExist(err):
-		// File exists but is unreadable/corrupt: surface it rather than
-		// silently regenerating a new identity and re-registering.
-		return LocalState{}, fmt.Errorf("load state: %w", err)
-	}
-
-	privKey, err := wgtypes.GeneratePrivateKey()
-	if err != nil {
-		return LocalState{}, fmt.Errorf("generate key: %w", err)
-	}
-
-	state, err = initFromHub(hubURL, apiKey, privKey)
-	if err != nil {
-		return LocalState{}, err
-	}
-
-	if err := storeJSON(statePath, state); err != nil {
-		return LocalState{}, fmt.Errorf("save state: %w", err)
-	}
-	return state, nil
-}
-
-func initFromHub(hubURL, apiKey string, privKey wgtypes.Key) (LocalState, error) {
-	wgPubKey := privKey.PublicKey()
-
-	signPubKey, signPrivKey, err := sign.GenerateKey(rand.Reader)
-	if err != nil {
-		return LocalState{}, fmt.Errorf("generate sign key: %w", err)
-	}
-
-	body, err := json.Marshal(m.PeerInitArgs{
-		WGPubKey:   wgPubKey[:],
-		SignPubKey: signPubKey[:],
-	})
-	if err != nil {
-		return LocalState{}, fmt.Errorf("json error: %w", err)
-	}
-
-	req, err := http.NewRequest(http.MethodPost, hubURL+"/peer/init/", bytes.NewReader(body))
-	if err != nil {
-		return LocalState{}, err
-	}
-	req.SetBasicAuth("", apiKey)
-	req.Header.Set("Content-Type", "application/json")
-
-	resp, err := http.DefaultClient.Do(req)
-	if err != nil {
-		return LocalState{}, fmt.Errorf("hub init: %w", err)
-	}
-	defer resp.Body.Close()
-
-	if resp.StatusCode != http.StatusOK {
-		return LocalState{}, fmt.Errorf("hub init: HTTP %d", resp.StatusCode)
-	}
-
-	var r m.PeerInitResp
-	if err := json.NewDecoder(resp.Body).Decode(&r); err != nil {
-		return LocalState{}, fmt.Errorf("hub init decode: %w", err)
-	}
-
-	if len(r.Network) != 4 {
-		return LocalState{}, fmt.Errorf("hub init: invalid network %v", r.Network)
-	}
-
-	netAddr := netip.AddrFrom4([4]byte(r.Network))
-	octets := netAddr.As4()
-	octets[3] = r.PeerIP
-	vpnIP := netip.AddrFrom4(octets)
-	vpnNet := netip.PrefixFrom(netAddr, 24)
-
-	var self *m.Peer
-	for i := range r.NetworkState.Peers {
-		if r.NetworkState.Peers[i].PeerIP == r.PeerIP {
-			self = &r.NetworkState.Peers[i]
-			break
-		}
-	}
-	if self == nil {
-		return LocalState{}, fmt.Errorf("hub init: no peer for own IP: %d", r.PeerIP)
-	}
-
-	public := self.IsPublic()
-
-	return LocalState{
-		PrivKey:     privKey,
-		SignKey:     *signPrivKey,
-		VPNIP:       vpnIP,
-		VPNNet:      vpnNet,
-		WGPort:      self.Port,
-		IsRelay:     self.Relay && public,
-		IsPublic:    public,
-		LocalDomain: r.LocalDomain,
-	}, nil
-}
-
-func (s LocalState) MarshalJSON() ([]byte, error) {
-	return json.Marshal(localStateJSON{
-		PrivKey:     base64.StdEncoding.EncodeToString(s.PrivKey[:]),
-		SignKey:     base64.StdEncoding.EncodeToString(s.SignKey[:]),
-		VPNIP:       s.VPNIP,
-		VPNNet:      s.VPNNet,
-		WGPort:      s.WGPort,
-		IsRelay:     s.IsRelay,
-		IsPublic:    s.IsPublic,
-		LocalDomain: s.LocalDomain,
-	})
-}
-
-func (s *LocalState) UnmarshalJSON(data []byte) error {
-	var j localStateJSON
-	if err := json.Unmarshal(data, &j); err != nil {
-		return err
-	}
-	keyBytes, err := base64.StdEncoding.DecodeString(j.PrivKey)
-	if err != nil {
-		return fmt.Errorf("decode key: %w", err)
-	}
-	key, err := wgtypes.NewKey(keyBytes)
-	if err != nil {
-		return fmt.Errorf("invalid key: %w", err)
-	}
-	signKeyBytes, err := base64.StdEncoding.DecodeString(j.SignKey)
-	if err != nil {
-		return fmt.Errorf("decode sign key: %w", err)
-	}
-	if len(signKeyBytes) != 64 {
-		return fmt.Errorf("invalid sign key length: %d", len(signKeyBytes))
-	}
-	*s = LocalState{
-		PrivKey:     key,
-		SignKey:     [64]byte(signKeyBytes),
-		VPNIP:       j.VPNIP,
-		VPNNet:      j.VPNNet,
-		WGPort:      j.WGPort,
-		IsRelay:     j.IsRelay,
-		IsPublic:    j.IsPublic,
-		LocalDomain: j.LocalDomain,
-	}
-	return nil
-}

peer/interface.go

@@ -0,0 +1,137 @@
+package peer
+
+import (
+	"fmt"
+	"io"
+	"net"
+	"os"
+	"syscall"
+
+	"golang.org/x/sys/unix"
+)
+
+func openInterface(network []byte, localIP byte, name string) (io.ReadWriteCloser, error) {
+	if len(network) != 4 {
+		return nil, fmt.Errorf("expected network to be 4 bytes, got %d", len(network))
+	}
+	ip := net.IPv4(network[0], network[1], network[2], localIP)
+
+	//////////////////////////
+	// Create TUN Interface //
+	//////////////////////////
+
+	tunFD, err := syscall.Open("/dev/net/tun", syscall.O_RDWR|unix.O_CLOEXEC, 0600)
+	if err != nil {
+		return nil, fmt.Errorf("failed to open TUN device: %w", err)
+	}
+
+	// New interface request.
+	req, err := unix.NewIfreq(name)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create new TUN interface request: %w", err)
+	}
+
+	// Flags:
+	//
+	// IFF_NO_PI => don't add packet info data to packets sent to the interface.
+	// IFF_TUN   => create a TUN device handling IP packets.
+	req.SetUint16(unix.IFF_NO_PI | unix.IFF_TUN)
+
+	err = unix.IoctlIfreq(tunFD, unix.TUNSETIFF, req)
+	if err != nil {
+		return nil, fmt.Errorf("failed to set TUN device settings: %w", err)
+	}
+
+	// Name may not be exactly the same?
+	name = req.Name()
+
+	/////////////
+	// Set MTU //
+	/////////////
+
+	// We need a socket file descriptor to set other options for some reason.
+	sockFD, err := unix.Socket(unix.AF_INET, unix.SOCK_DGRAM, unix.IPPROTO_IP)
+	if err != nil {
+		return nil, fmt.Errorf("failed to open socket: %w", err)
+	}
+	defer unix.Close(sockFD)
+
+	req, err = unix.NewIfreq(name)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create MTU interface request: %w", err)
+	}
+
+	req.SetUint32(if_mtu)
+	if err = unix.IoctlIfreq(sockFD, unix.SIOCSIFMTU, req); err != nil {
+		return nil, fmt.Errorf("failed to set interface MTU: %w", err)
+	}
+
+	//////////////////////
+	// Set Queue Length //
+	//////////////////////
+
+	req, err = unix.NewIfreq(name)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create IP interface request: %w", err)
+	}
+
+	req.SetUint16(if_queue_len)
+	if err = unix.IoctlIfreq(sockFD, unix.SIOCSIFTXQLEN, req); err != nil {
+		return nil, fmt.Errorf("failed to set interface queue length: %w", err)
+	}
+
+	/////////////////////
+	// Set IP and Mask //
+	/////////////////////
+
+	req, err = unix.NewIfreq(name)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create IP interface request: %w", err)
+	}
+
+	if err := req.SetInet4Addr(ip.To4()); err != nil {
+		return nil, fmt.Errorf("failed to set interface request IP: %w", err)
+	}
+
+	if err = unix.IoctlIfreq(sockFD, unix.SIOCSIFADDR, req); err != nil {
+		return nil, fmt.Errorf("failed to set interface IP: %w", err)
+	}
+
+	// SET MASK - must happen after setting address.
+	req, err = unix.NewIfreq(name)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create mask interface request: %w", err)
+	}
+
+	if err := req.SetInet4Addr(net.IPv4(255, 255, 255, 0).To4()); err != nil {
+		return nil, fmt.Errorf("failed to set interface request mask: %w", err)
+	}
+
+	if err := unix.IoctlIfreq(sockFD, unix.SIOCSIFNETMASK, req); err != nil {
+		return nil, fmt.Errorf("failed to set interface mask: %w", err)
+	}
+
+	////////////////////////
+	// Bring Interface Up //
+	////////////////////////
+
+	req, err = unix.NewIfreq(name)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create up interface request: %w", err)
+	}
+
+	// Get current flags.
+	if err = unix.IoctlIfreq(sockFD, unix.SIOCGIFFLAGS, req); err != nil {
+		return nil, fmt.Errorf("failed to get interface flags: %w", err)
+	}
+
+	flags := req.Uint16() | unix.IFF_UP | unix.IFF_RUNNING
+
+	// Set UP flag / broadcast flags.
+	req.SetUint16(flags)
+	if err = unix.IoctlIfreq(sockFD, unix.SIOCSIFFLAGS, req); err != nil {
+		return nil, fmt.Errorf("failed to set interface up: %w", err)
+	}
+
+	return os.NewFile(uintptr(tunFD), "tun"), nil
+}

peer/interfaces.go

@@ -1,28 +0,0 @@
-package peer
-
-import (
-	"net/netip"
-	"vppn/peer/control"
-
-	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
-)
-
-// WGDevice is the subset of wginterface.Device used by App.
-type WGDevice interface {
-	Name() string
-	Peers() ([]wgtypes.Peer, error)
-	AddPeer(pubKey wgtypes.Key) error
-	AddDirect(pubKey wgtypes.Key, endpoint netip.AddrPort, vpnIP netip.Addr) error
-	SetRelay(pubKey wgtypes.Key, endpoint netip.AddrPort, network netip.Prefix) error
-	AddProbe(pubKey wgtypes.Key, endpoint netip.AddrPort) error
-	Promote(pubKey wgtypes.Key, vpnIP netip.Addr) error
-	RemovePeer(pubKey wgtypes.Key) error
-}
-
-// ControlConn sends pings to peers over the VPN control port.
-// Reading is handled separately via run, which feeds the App's pingCh.
-// buf is a caller-provided scratch buffer (at least control.Size bytes) used to
-// marshal the ping; the caller reuses one across sends.
-type ControlConn interface {
-	SendPing(dst netip.AddrPort, ping control.Ping, buf []byte) error
-}

peer/json.go

@@ -1,36 +0,0 @@
-package peer
-
-import (
-	"encoding/json"
-	"os"
-	"path/filepath"
-)
-
-func loadJSON(path string, target any) error {
-	data, err := os.ReadFile(path)
-	if err != nil {
-		return err
-	}
-	return json.Unmarshal(data, target)
-}
-
-func storeJSON(path string, obj any) error {
-	if err := os.MkdirAll(filepath.Dir(path), 0700); err != nil {
-		return err
-	}
-	data, err := json.MarshalIndent(obj, "", "  ")
-	if err != nil {
-		return err
-	}
-
-	tmpPath := path + ".tmp"
-	if err := os.WriteFile(tmpPath, data, 0600); err != nil {
-		return err
-	}
-
-	if err := os.Rename(tmpPath, path); err != nil {
-		os.Remove(tmpPath)
-		return err
-	}
-	return nil
-}

peer/main.go

@@ -0,0 +1,207 @@
+package peer
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"net"
+	"net/http"
+	"net/netip"
+	"os"
+	"time"
+)
+
+// Usage:
+//
+// vppn netName run
+// vppn netName status
+func Main2() {
+	printUsage := func() {
+		fmt.Fprintf(os.Stderr, `%s COMMAND [ARGUMENTS...]
+
+Available commands:
+    run
+    status
+    hosts
+`, os.Args[0])
+		os.Exit(1)
+	}
+
+	if len(os.Args) < 2 {
+		printUsage()
+	}
+
+	command := os.Args[1]
+
+	switch command {
+	case "run":
+		main_run()
+	case "status":
+		main_status()
+	case "hosts":
+		main_hosts()
+	default:
+		printUsage()
+	}
+}
+
+// ----------------------------------------------------------------------------
+
+type mainArgs struct {
+	NetName    string
+	HubAddress string
+	APIKey     string
+}
+
+func main_run() {
+	printUsage := func() {
+		fmt.Fprintf(os.Stderr, `Usage: %s run NETWORK_NAME HUB_ADDRESS API_KEY
+
+    NETWORK_NAME
+        Unique name of the network interface created. The network name
+        shouldn't change between invocations of the application.
+
+    HUB_ADDRESS
+        The address of the hub server. This should also contain the scheme, for
+        example https://hub.domain.com/.
+
+    API_KEY
+        The API key assigned to this peer by the hub.
+
+`, os.Args[0])
+		os.Exit(1)
+	}
+
+	if len(os.Args) != 5 {
+		printUsage()
+	}
+
+	args := mainArgs{
+		NetName:    os.Args[2],
+		HubAddress: os.Args[3],
+		APIKey:     os.Args[4],
+	}
+
+	newPeerMain(args).Run()
+}
+
+// ----------------------------------------------------------------------------
+
+func main_status() {
+	printUsage := func() {
+		fmt.Fprintf(os.Stderr, `Usage: %s status NETWORK_NAME
+
+    NETWORK_NAME
+        Unique name of the network interface created.
+
+`, os.Args[0])
+		os.Exit(1)
+	}
+
+	if len(os.Args) != 3 {
+		printUsage()
+	}
+
+	netName := os.Args[2]
+	report := fetchStatusReport(netName)
+
+	fmt.Printf("\n%s Status\n\n", netName)
+
+	if len(report.Network) != 4 {
+		fmt.Printf("Network: %v\n\n", report.Network)
+	} else {
+		nw := report.Network
+		fmt.Printf("%-8s %d.%d.%d.%d/24\n", "Network", nw[0], nw[1], nw[2], nw[3])
+	}
+
+	if report.RelayPeerIP != 0 {
+		fmt.Printf("%-8s %d\n\n", "Relay", report.RelayPeerIP)
+	} else {
+		fmt.Printf("%-8s -\n\n", "Relay")
+	}
+
+	for _, status := range report.Remotes {
+		fmt.Printf("%3d %s\n", status.PeerIP, status.Name)
+		fmt.Printf("    %-11s %v\n", "Up", status.Up)
+
+		pubIP, ok := netip.AddrFromSlice(status.PublicIP)
+		if ok {
+			fmt.Printf("    %-11s %v\n", "Public IP", pubIP)
+		} else {
+			fmt.Printf("    %-11s\n", "Public IP")
+		}
+		fmt.Printf("    %-11s %d\n", "Port", status.Port)
+		fmt.Printf("    %-11s %v\n", "Relay", status.Relay)
+		fmt.Printf("    %-11s %v\n", "Server", status.Server)
+		fmt.Printf("    %-11s %v\n", "Direct", status.Direct)
+		if status.DirectAddr.IsValid() {
+			fmt.Printf("    %-11s %v\n", "Address", status.DirectAddr)
+		}
+		fmt.Println("")
+	}
+}
+
+// ----------------------------------------------------------------------------
+
+func main_hosts() {
+	printUsage := func() {
+		fmt.Fprintf(os.Stderr, `Usage: %s hosts NETWORK_NAME
+
+    NETWORK_NAME
+        Unique name of the network interface created.
+
+`, os.Args[0])
+		os.Exit(1)
+	}
+
+	if len(os.Args) != 3 {
+		printUsage()
+	}
+
+	netName := os.Args[2]
+	state, err := loadNetworkState(netName)
+	if err != nil {
+		log.Fatalf("Failed to load network state: %v", err)
+	}
+
+	config, err := loadPeerConfig(netName)
+	if err != nil {
+		log.Fatalf("Failed to load config: %v", err)
+	}
+
+	nw := config.Network
+	for _, peer := range state.Peers {
+		if peer == nil {
+			continue
+		}
+		fmt.Printf("%d.%d.%d.%d %s\n",
+			nw[0], nw[1], nw[2], peer.PeerIP, peer.Name)
+	}
+	fmt.Println("")
+}
+
+// ----------------------------------------------------------------------------
+
+func fetchStatusReport(netName string) StatusReport {
+	client := http.Client{
+		Transport: &http.Transport{
+			Dial: func(_, _ string) (net.Conn, error) {
+				return net.Dial("unix", statusSocketPath(netName))
+			},
+		},
+		Timeout: 8 * time.Second,
+	}
+
+	getURL := "http://unix" + statusSocketPath(netName)
+	resp, err := client.Get(getURL)
+	if err != nil {
+		log.Fatalf("Failed to get response: %v", err)
+	}
+
+	report := StatusReport{}
+	if err := json.NewDecoder(resp.Body).Decode(&report); err != nil {
+		log.Fatalf("Failed to decode status report: %v", err)
+	}
+
+	return report
+}

peer/main_test.go

@@ -0,0 +1,5 @@
+package peer
+
+func newBuf() []byte {
+	return make([]byte, bufferSize)
+}

peer/mcreader.go

@@ -0,0 +1,47 @@
+package peer
+
+import (
+	"log"
+	"net"
+	"time"
+)
+
+func RunMCReader(g Globals) {
+	for {
+		runMCReaderInner(g)
+		time.Sleep(broadcastErrorTimeoutInterval)
+	}
+}
+
+func runMCReaderInner(g Globals) {
+	var (
+		buf  = make([]byte, bufferSize)
+		logf = func(s string, args ...any) {
+			log.Printf("[MCReader] "+s, args...)
+		}
+	)
+
+	conn, err := net.ListenMulticastUDP("udp", nil, multicastAddr)
+	if err != nil {
+		logf("Failed to bind to multicast address: %v", err)
+		return
+	}
+
+	for {
+		conn.SetReadDeadline(time.Now().Add(32 * time.Second))
+		n, remoteAddr, err := conn.ReadFromUDPAddrPort(buf[:bufferSize])
+		if err != nil {
+			logf("Failed to read from UDP port): %v", err)
+			return
+		}
+
+		buf = buf[:n]
+		h, ok := headerFromLocalDiscoveryPacket(buf)
+		if !ok {
+			logf("Failed to open discovery packet?")
+			continue
+		}
+
+		g.RemotePeers[h.SourceIP].Load().HandleLocalDiscoveryPacket(h, remoteAddr, buf)
+	}
+}

peer/mcreader_test.go

@@ -0,0 +1,132 @@
+package peer
+
+/*
+type mcMockConn struct {
+	packets chan []byte
+}
+
+func newMCMockConn() *mcMockConn {
+	return &mcMockConn{make(chan []byte, 32)}
+}
+
+func (c *mcMockConn) WriteToUDP(in []byte, addr *net.UDPAddr) (int, error) {
+	c.packets <- bytes.Clone(in)
+	return len(in), nil
+}
+
+func (c *mcMockConn) ReadFromUDPAddrPort(b []byte) (n int, addr netip.AddrPort, err error) {
+	buf := <-c.packets
+	b = b[:len(buf)]
+	copy(b, buf)
+	return len(b), netip.AddrPort{}, nil
+}
+
+func TestMCReader(t *testing.T) {
+	keys := generateKeys()
+	super := &mockControlMsgHandler{}
+	conn := newMCMockConn()
+
+	peers := [256]*atomic.Pointer[RemotePeer]{}
+	peer := &RemotePeer{
+		IP:         1,
+		Up:         true,
+		PubSignKey: keys.PubSignKey,
+	}
+	peers[1] = &atomic.Pointer[RemotePeer]{}
+	peers[1].Store(peer)
+
+	w := newMCWriter(conn, 1, keys.PrivSignKey)
+	r := newMCReader(conn, super, peers)
+
+	w.SendLocalDiscovery()
+	r.handleNextPacket()
+
+	if len(super.Messages) != 1 {
+		t.Fatal(super.Messages)
+	}
+	msg, ok := super.Messages[0].(controlMsg[PacketLocalDiscovery])
+	if !ok || msg.SrcIP != 1 {
+		t.Fatal(ok, msg)
+	}
+}
+
+func TestMCReader_noHeader(t *testing.T) {
+	keys := generateKeys()
+	super := &mockControlMsgHandler{}
+	conn := newMCMockConn()
+
+	peers := [256]*atomic.Pointer[RemotePeer]{}
+	peer := &RemotePeer{
+		IP:         1,
+		Up:         true,
+		PubSignKey: keys.PubSignKey,
+	}
+	peers[1] = &atomic.Pointer[RemotePeer]{}
+	peers[1].Store(peer)
+
+	r := newMCReader(conn, super, peers)
+	conn.WriteToUDP([]byte("0123546789"), nil)
+	r.handleNextPacket()
+
+	if len(super.Messages) != 0 {
+		t.Fatal(super.Messages)
+	}
+}
+
+func TestMCReader_noPeer(t *testing.T) {
+	keys := generateKeys()
+	super := &mockControlMsgHandler{}
+	conn := newMCMockConn()
+
+	peers := [256]*atomic.Pointer[RemotePeer]{}
+	peer := &RemotePeer{
+		IP:         1,
+		Up:         true,
+		PubSignKey: keys.PubSignKey,
+	}
+	peers[1] = &atomic.Pointer[RemotePeer]{}
+	peers[2] = &atomic.Pointer[RemotePeer]{}
+	peers[1].Store(peer)
+
+	w := newMCWriter(conn, 2, keys.PrivSignKey)
+	r := newMCReader(conn, super, peers)
+
+	w.SendLocalDiscovery()
+	r.handleNextPacket()
+
+	if len(super.Messages) != 0 {
+		t.Fatal(super.Messages)
+	}
+}
+
+func TestMCReader_badSignature(t *testing.T) {
+	keys := generateKeys()
+	super := &mockControlMsgHandler{}
+	conn := newMCMockConn()
+
+	peers := [256]*atomic.Pointer[RemotePeer]{}
+	peer := &RemotePeer{
+		IP:         1,
+		Up:         true,
+		PubSignKey: keys.PubSignKey,
+	}
+	peers[1] = &atomic.Pointer[RemotePeer]{}
+	peers[1].Store(peer)
+
+	w := newMCWriter(conn, 1, keys.PrivSignKey)
+	w.SendLocalDiscovery()
+
+	// Break signing.
+	packet := <-conn.packets
+	packet[0]++
+	conn.packets <- packet
+
+	r := newMCReader(conn, super, peers)
+
+	r.handleNextPacket()
+
+	if len(super.Messages) != 0 {
+		t.Fatal(super.Messages)
+	}
+}
+*/

peer/mcwriter.go

@@ -0,0 +1,54 @@
+package peer
+
+import (
+	"log"
+	"net"
+	"time"
+
+	"golang.org/x/crypto/nacl/sign"
+)
+
+func createLocalDiscoveryPacket(localIP byte, signingKey []byte) []byte {
+	h := Header{
+		SourceIP: localIP,
+		DestIP:   255,
+	}
+	buf := make([]byte, headerSize)
+	h.Marshal(buf)
+	out := make([]byte, headerSize+signingOverhead)
+	return sign.Sign(out[:0], buf, (*[64]byte)(signingKey))
+}
+
+func headerFromLocalDiscoveryPacket(pkt []byte) (h Header, ok bool) {
+	if len(pkt) != headerSize+signingOverhead {
+		return
+	}
+
+	h.Parse(pkt[signingOverhead:])
+	ok = true
+	return
+}
+
+func verifyLocalDiscoveryPacket(pkt, buf []byte, pubSignKey []byte) bool {
+	_, ok := sign.Open(buf[:0], pkt, (*[32]byte)(pubSignKey))
+	return ok
+}
+
+// ----------------------------------------------------------------------------
+
+func RunMCWriter(localIP byte, signingKey []byte) {
+	discoveryPacket := createLocalDiscoveryPacket(localIP, signingKey)
+
+	conn, err := net.ListenMulticastUDP("udp", nil, multicastAddr)
+	if err != nil {
+		log.Fatalf("[MCWriter] Failed to bind to multicast address: %v", err)
+	}
+
+	for range time.Tick(broadcastInterval) {
+		log.Printf("[MCWriter] Broadcasting on %v...", multicastAddr)
+		_, err := conn.WriteToUDP(discoveryPacket, multicastAddr)
+		if err != nil {
+			log.Printf("[MCWriter] Failed to write multicast: %v", err)
+		}
+	}
+}

peer/mcwriter_test.go

@@ -0,0 +1,98 @@
+package peer
+
+/*
+// ----------------------------------------------------------------------------
+
+// Testing that we can create and verify a local discovery packet.
+func TestVerifyLocalDiscoveryPacket_valid(t *testing.T) {
+	keys := generateKeys()
+
+	created := createLocalDiscoveryPacket(55, keys.PrivSignKey)
+
+	header, ok := headerFromLocalDiscoveryPacket(created)
+	if !ok {
+		t.Fatal(ok)
+	}
+	if header.SourceIP != 55 || header.DestIP != 255 {
+		t.Fatal(header)
+	}
+
+	if !verifyLocalDiscoveryPacket(created, make([]byte, 1024), keys.PubSignKey) {
+		t.Fatal("Not valid")
+	}
+}
+
+// Testing that we don't try to parse short packets.
+func TestVerifyLocalDiscoveryPacket_tooShort(t *testing.T) {
+	keys := generateKeys()
+
+	created := createLocalDiscoveryPacket(55, keys.PrivSignKey)
+
+	_, ok := headerFromLocalDiscoveryPacket(created[:len(created)-1])
+	if ok {
+		t.Fatal(ok)
+	}
+}
+
+// Testing that modifying a packet makes it invalid.
+func TestVerifyLocalDiscoveryPacket_invalid(t *testing.T) {
+	keys := generateKeys()
+
+	created := createLocalDiscoveryPacket(55, keys.PrivSignKey)
+	buf := make([]byte, 1024)
+	for i := range created {
+		modified := bytes.Clone(created)
+		modified[i]++
+		if verifyLocalDiscoveryPacket(modified, buf, keys.PubSignKey) {
+			t.Fatal("Verification should have failed.")
+		}
+	}
+}
+
+// ----------------------------------------------------------------------------
+
+type testUDPWriter struct {
+	written [][]byte
+}
+
+func (w *testUDPWriter) WriteToUDP(b []byte, addr *net.UDPAddr) (int, error) {
+	w.written = append(w.written, bytes.Clone(b))
+	return len(b), nil
+}
+
+func (w *testUDPWriter) Written() [][]byte {
+	out := w.written
+	w.written = [][]byte{}
+	return out
+}
+
+// ----------------------------------------------------------------------------
+
+// Testing that the mcWriter sends local discovery packets as expected.
+func TestMCWriter_SendLocalDiscovery(t *testing.T) {
+	keys := generateKeys()
+	writer := &testUDPWriter{}
+
+	mcw := newMCWriter(writer, 42, keys.PrivSignKey)
+	mcw.SendLocalDiscovery()
+
+	out := writer.Written()
+	if len(out) != 1 {
+		t.Fatal(out)
+	}
+
+	pkt := out[0]
+
+	header, ok := headerFromLocalDiscoveryPacket(pkt)
+	if !ok {
+		t.Fatal(ok)
+	}
+	if header.SourceIP != 42 || header.DestIP != 255 {
+		t.Fatal(header)
+	}
+
+	if !verifyLocalDiscoveryPacket(pkt, make([]byte, 1024), keys.PubSignKey) {
+		t.Fatal("Verification should succeed.")
+	}
+}
+*/

peer/mock-iface_test.go

@@ -0,0 +1,31 @@
+package peer
+
+import "bytes"
+
+type TestIFace struct {
+	out *bytes.Buffer // Toward the network.
+	in  *bytes.Buffer // From the network
+}
+
+func NewTestIFace() *TestIFace {
+	return &TestIFace{
+		out: &bytes.Buffer{},
+		in:  &bytes.Buffer{},
+	}
+}
+
+func (iface *TestIFace) Write(b []byte) (int, error) {
+	return iface.in.Write(b)
+}
+
+func (iface *TestIFace) Read(b []byte) (int, error) {
+	return iface.out.Read(b)
+}
+
+func (iface *TestIFace) UserWrite(b []byte) (int, error) {
+	return iface.out.Write(b)
+}
+
+func (iface *TestIFace) UserRead(b []byte) (int, error) {
+	return iface.in.Read(b)
+}

peer/mock-network_test.go

@@ -0,0 +1,80 @@
+package peer
+
+import (
+	"bytes"
+	"net"
+	"net/netip"
+	"sync"
+)
+
+type TestPacket struct {
+	Addr netip.AddrPort
+	Data []byte
+}
+
+type TestNetwork struct {
+	lock    sync.Mutex
+	packets map[netip.AddrPort]chan TestPacket
+}
+
+func NewTestNetwork() *TestNetwork {
+	return &TestNetwork{packets: map[netip.AddrPort]chan TestPacket{}}
+}
+
+func (n *TestNetwork) NewUDPConn(localAddr netip.AddrPort) *TestUDPConn {
+	n.lock.Lock()
+	defer n.lock.Unlock()
+	if _, ok := n.packets[localAddr]; !ok {
+		n.packets[localAddr] = make(chan TestPacket, 1024)
+	}
+	return &TestUDPConn{
+		addr:    localAddr,
+		n:       n,
+		packets: n.packets[localAddr],
+	}
+}
+
+func (n *TestNetwork) write(b []byte, from, to netip.AddrPort) {
+	n.lock.Lock()
+	defer n.lock.Unlock()
+	if _, ok := n.packets[to]; !ok {
+		n.packets[to] = make(chan TestPacket, 1024)
+	}
+	n.packets[to] <- TestPacket{
+		Addr: from,
+		Data: bytes.Clone(b),
+	}
+}
+
+type TestUDPConn struct {
+	addr    netip.AddrPort
+	n       *TestNetwork
+	packets chan TestPacket
+}
+
+func (c *TestUDPConn) WriteToUDPAddrPort(b []byte, addr netip.AddrPort) (int, error) {
+	c.n.write(b, c.addr, addr)
+	return len(b), nil
+}
+
+func (c *TestUDPConn) WriteToUDP(b []byte, addr *net.UDPAddr) (int, error) {
+	return c.WriteToUDPAddrPort(b, addr.AddrPort())
+}
+
+func (c *TestUDPConn) ReadFromUDPAddrPort(b []byte) (n int, addr netip.AddrPort, err error) {
+	pkt := <-c.packets
+	b = b[:len(pkt.Data)]
+	copy(b, pkt.Data)
+	return len(b), pkt.Addr, nil
+}
+
+func (c *TestUDPConn) Packets() (out []TestPacket) {
+	for {
+		select {
+		case pkt := <-c.packets:
+			out = append(out, pkt)
+		default:
+			return
+		}
+	}
+}

peer/multicast/broadcaster.go

@@ -1,62 +0,0 @@
-package multicast
-
-import (
-	"log"
-	"net"
-	"net/netip"
-	"time"
-
-	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
-)
-
-var addr = net.UDPAddrFromAddrPort(netip.AddrPortFrom(
-	netip.AddrFrom4([4]byte{224, 0, 0, 157}),
-	4560))
-
-func Broadcast(
-	selfVPNIP netip.Addr,
-	pubKey wgtypes.Key,
-	wgPort uint16,
-	signKey *[64]byte,
-) {
-	for {
-		broadcastInner(selfVPNIP, pubKey, wgPort, signKey)
-		time.Sleep(errorTimeout)
-	}
-}
-
-func broadcastInner(selfVPNIP netip.Addr, pubKey wgtypes.Key, wgPort uint16, signKey *[64]byte) {
-	conn, err := net.ListenMulticastUDP("udp", nil, addr)
-	if err != nil {
-		log.Printf("[MCBroadcast] bind: %v", err)
-		return
-	}
-	defer conn.Close()
-
-	buf := make([]byte, BufferSize)
-	packet := Packet{
-		PeerIP:   selfVPNIP.As4()[3],
-		WGPubKey: pubKey,
-		WGPort:   wgPort,
-	}
-
-	// Re-sign on each send so the timestamp is fresh; a stale timestamp would be
-	// dropped by receivers' freshness gate.
-	send := func() error {
-		packet.Timestamp = time.Now().Unix()
-		payload := packet.Marshal(buf, signKey)
-		_, err := conn.WriteToUDP(payload, addr)
-		return err
-	}
-
-	if err := send(); err != nil {
-		log.Printf("[MCBroadcast] write: %v", err)
-	}
-
-	for range time.Tick(broadcastInterval) {
-		if err := send(); err != nil {
-			log.Printf("[MCBroadcast] write: %v", err)
-			return
-		}
-	}
-}

peer/multicast/global.go

@@ -1,9 +0,0 @@
-package multicast
-
-import "time"
-
-const (
-	errorTimeout      = 16 * time.Second
-	broadcastInterval = 16 * time.Second
-	maxPacketAge      = time.Minute
-)

peer/multicast/packet.go

@@ -1,54 +0,0 @@
-package multicast
-
-import (
-	"encoding/binary"
-	"net/netip"
-
-	"golang.org/x/crypto/nacl/sign"
-)
-
-const (
-	BufferSize       = packetSize + SignedPacketSize
-	SignedPacketSize = packetSize + signSize
-	packetSize       = 43
-	signSize         = 64
-)
-
-// Layout:
-//
-// [0]      final octet of the sender's VPN IP
-// [1:33]   WG public key
-// [33:35]  WG listen port (big-endian uint16)
-// [35:43]  send time, Unix seconds (big-endian int64) — freshness/replay gate
-type Packet struct {
-	PeerIP    byte       // Final octet of the sender's VPN IP.
-	WGPubKey  [32]byte   // WG public key.
-	WGPort    uint16     // WG listen port.
-	Timestamp int64      // Unix timestamp.
-	Src       netip.Addr // Source of packet.
-	Signed    []byte     // Raw signed message for verification (incoming packet).
-}
-
-// Marshal the packet into a buffer with prefixed signature.
-func (p Packet) Marshal(buf []byte, signKey *[64]byte) []byte {
-	buf[0] = p.PeerIP
-	copy(buf[1:33], p.WGPubKey[:])
-	binary.BigEndian.PutUint16(buf[33:35], p.WGPort)
-	binary.BigEndian.PutUint64(buf[35:43], uint64(p.Timestamp))
-	return sign.Sign(buf[packetSize:packetSize], buf[:packetSize], signKey)
-}
-
-func (p Packet) Verify(buf []byte, pubKey *[32]byte) bool {
-	_, ok := sign.Open(buf, p.Signed, pubKey)
-	return ok
-}
-
-func Unmarshal(signed []byte) (p Packet) {
-	buf := signed[signSize:]
-	p.PeerIP = buf[0]
-	copy(p.WGPubKey[:], buf[1:33])
-	p.WGPort = binary.BigEndian.Uint16(buf[33:35])
-	p.Timestamp = int64(binary.BigEndian.Uint64(buf[35:43]))
-	p.Signed = signed
-	return
-}

peer/multicast/packet_test.go

@@ -1,38 +0,0 @@
-package multicast
-
-import (
-	"crypto/rand"
-	"testing"
-
-	"golang.org/x/crypto/nacl/sign"
-)
-
-func TestPacket(t *testing.T) {
-	pub, priv, err := sign.GenerateKey(rand.Reader)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	p := Packet{
-		PeerIP:    10,
-		WGPubKey:  [32]byte{1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2},
-		WGPort:    44,
-		Timestamp: 12948893,
-	}
-
-	buf := make([]byte, BufferSize)
-	signed := p.Marshal(buf, priv)
-	if len(signed) != SignedPacketSize {
-		t.Fatalf("signed length = %d, want %d", len(signed), SignedPacketSize)
-	}
-
-	got := Unmarshal(signed)
-	if got.PeerIP != p.PeerIP || got.WGPubKey != p.WGPubKey ||
-		got.WGPort != p.WGPort || got.Timestamp != p.Timestamp {
-		t.Fatalf("round-trip mismatch:\n got %+v\nwant %+v", got, p)
-	}
-
-	if !got.Verify(nil, pub) {
-		t.Error("signature did not verify")
-	}
-}

peer/multicast/receiver.go

@@ -1,61 +0,0 @@
-package multicast
-
-import (
-	"bytes"
-	"fmt"
-	"log"
-	"net"
-	"net/netip"
-	"time"
-)
-
-func Receiver(vpnNet netip.Prefix, selfVPNIP netip.Addr, ch chan<- Packet) {
-	for {
-		if err := receiver(vpnNet, selfVPNIP, ch); err != nil {
-			log.Printf("[MCReader] %v", err)
-		}
-		time.Sleep(errorTimeout)
-	}
-}
-
-func receiver(vpnNet netip.Prefix, selfVPNIP netip.Addr, ch chan<- Packet) error {
-	selfIP := selfVPNIP.As4()[3]
-
-	conn, err := net.ListenMulticastUDP("udp", nil, addr)
-	if err != nil {
-		return fmt.Errorf("bind: %w", err)
-	}
-	defer conn.Close()
-
-	buf := make([]byte, BufferSize+1) // +1 to detect oversized packets
-
-	for {
-		conn.SetReadDeadline(time.Now().Add(32 * time.Second))
-		n, src, err := conn.ReadFromUDPAddrPort(buf)
-		if err != nil {
-			if ne, ok := err.(net.Error); ok && ne.Timeout() {
-				continue
-			}
-			return fmt.Errorf("read: %w", err)
-		}
-
-		if n != SignedPacketSize {
-			continue
-		}
-
-		packet := Unmarshal(buf[:n])
-
-		if packet.PeerIP == selfIP {
-			continue
-		}
-
-		age := time.Since(time.Unix(packet.Timestamp, 0))
-		if age > maxPacketAge || age < -maxPacketAge {
-			continue
-		}
-
-		packet.Signed = bytes.Clone(packet.Signed)
-		packet.Src = src.Addr().Unmap()
-		ch <- packet
-	}
-}

peer/network_state.go

@@ -1,18 +0,0 @@
-package peer
-
-import "vppn/m"
-
-// loadNetworkState reads a cached network state from disk. Any error (most
-// commonly a missing file on first run) is returned to the caller, which
-// treats it as "no cache available".
-func loadNetworkState(path string) (m.NetworkState, error) {
-	var state m.NetworkState
-	err := loadJSON(path, &state)
-	return state, err
-}
-
-// saveNetworkState writes state to path atomically (see storeJSON), so a crash
-// mid-write cannot leave a corrupt cache.
-func saveNetworkState(path string, state m.NetworkState) error {
-	return storeJSON(path, state)
-}

peer/network_state_test.go

@@ -1,56 +0,0 @@
-package peer
-
-import (
-	"net/netip"
-	"path/filepath"
-	"reflect"
-	"testing"
-
-	"vppn/m"
-)
-
-func TestNetworkState_RoundTrip(t *testing.T) {
-	path := filepath.Join(t.TempDir(), "network.json")
-
-	var sign1 [32]byte
-	copy(sign1[:], []byte("0123456789abcdef0123456789abcdef"))
-
-	state := m.NetworkState{Peers: []m.Peer{
-		{
-			PeerIP:     1,
-			Name:       "hub",
-			Addr4:      netip.MustParseAddr("10.11.12.1"),
-			Port:       51820,
-			Relay:      true,
-			WGPubKey:   mustKey(t),
-			SignPubKey: sign1,
-		},
-		{
-			PeerIP:   10,
-			Name:     "laptop",
-			Addr4:    netip.MustParseAddr("10.11.12.10"),
-			Port:     51820,
-			WGPubKey: mustKey(t),
-		},
-	}}
-
-	if err := saveNetworkState(path, state); err != nil {
-		t.Fatal(err)
-	}
-
-	got, err := loadNetworkState(path)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if !reflect.DeepEqual(got, state) {
-		t.Errorf("round-trip mismatch:\n got: %+v\nwant: %+v", got.Peers[1], state.Peers[1])
-	}
-}
-
-func TestNetworkState_LoadMissing(t *testing.T) {
-	path := filepath.Join(t.TempDir(), "does-not-exist.json")
-	if _, err := loadNetworkState(path); err == nil {
-		t.Fatal("expected error loading missing cache, got nil")
-	}
-}

peer/new.go

@@ -1,109 +0,0 @@
-package peer
-
-import (
-	"fmt"
-	"net/netip"
-
-	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
-
-	"vppn/m"
-	"vppn/peer/multicast"
-	"vppn/peer/wginterface"
-)
-
-// New constructs an App, creates the WireGuard interface, and starts the
-// background goroutines (hub poller, multicast, control conn reader).
-// The caller should invoke Run() to start the event loop.
-func New(
-	state LocalState,
-	hubURL, apiKey string,
-	ifaceName string,
-	localDomain string,
-	networkStatePath string,
-) (*App, error) {
-
-	a4 := state.VPNIP.As4()
-	if err := wginterface.Create(ifaceName, a4[:], 24); err != nil {
-		return nil, fmt.Errorf("create WG interface: %w", err)
-	}
-
-	dev, err := wginterface.Open(ifaceName)
-	if err != nil {
-		_ = wginterface.Delete(ifaceName)
-		return nil, fmt.Errorf("open WG device: %w", err)
-	}
-
-	cc, err := newUDPControlConn(state.VPNIP, ControlPort)
-	if err != nil {
-		_ = dev.Close()
-		_ = wginterface.Delete(ifaceName)
-		return nil, fmt.Errorf("control conn: %w", err)
-	}
-
-	cleanup := func() {
-		_ = cc.Close()
-		_ = dev.Close()
-		_ = wginterface.Delete(ifaceName)
-	}
-
-	if err := dev.Configure(state.PrivKey, int(state.WGPort)); err != nil {
-		cleanup()
-		return nil, fmt.Errorf("configure WG device: %w", err)
-	}
-
-	if state.IsRelay {
-		if err := dev.EnableForwarding(); err != nil {
-			cleanup()
-			return nil, fmt.Errorf("enable forwarding: %w", err)
-		}
-	}
-
-	pingCh := make(chan PingEvent)
-	hubAddCh := make(chan m.Peer)
-	hubRemoveCh := make(chan wgtypes.Key)
-	multicastCh := make(chan multicast.Packet)
-
-	poller, err := NewHubPoller(
-		state.VPNIP,
-		state.VPNNet,
-		hubURL,
-		apiKey,
-		networkStatePath,
-		hubAddCh,
-		hubRemoveCh)
-	if err != nil {
-		cleanup()
-		return nil, fmt.Errorf("hub poller: %w", err)
-	}
-
-	go cc.run(pingCh)
-	go poller.Run()
-
-	if !state.IsPublic {
-		go multicast.Broadcast(state.VPNIP, state.PrivKey.PublicKey(), state.WGPort, &state.SignKey)
-		go multicast.Receiver(state.VPNNet, state.VPNIP, multicastCh)
-	}
-
-	return &App{
-		vpnIP:       state.VPNIP,
-		vpnNet:      state.VPNNet,
-		privKey:     state.PrivKey,
-		pubKey:      state.PrivKey.PublicKey(),
-		isRelay:     state.IsRelay,
-		isPublic:    state.IsPublic,
-		localDomain: localDomain,
-
-		dev:         dev,
-		controlConn: cc,
-
-		peersByKey: make(map[wgtypes.Key]*Peer),
-		peersByIP:  make(map[netip.Addr]*Peer),
-
-		scratch: make([]byte, scratchSize),
-
-		hubAddCh:    hubAddCh,
-		hubRemoveCh: hubRemoveCh,
-		pingCh:      pingCh,
-		multicastCh: multicastCh,
-	}, nil
-}

peer/on_hub.go

@@ -1,114 +0,0 @@
-package peer
-
-import (
-	"log"
-	"math"
-	"net/netip"
-	"time"
-
-	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
-
-	"vppn/m"
-	"vppn/peer/control"
-)
-
-func (a *App) onAddPeer(p m.Peer) {
-	a.onRemovePeer(p.WGPubKey)
-
-	octets := a.vpnNet.Addr().As4()
-	octets[3] = p.PeerIP
-	vpnIP := netip.AddrFrom4(octets)
-
-	peer := &Peer{
-		wgPeer:     wgtypes.Peer{PublicKey: p.WGPubKey},
-		VPNIP:      vpnIP,
-		Name:       p.Name,
-		IsRelay:    p.Relay,
-		IsPublic:   p.IsPublic(),
-		EndpointV4: p.Endpoint4(),
-		EndpointV6: p.Endpoint6(),
-		RTT:        time.Duration(math.MaxInt64) * time.Nanosecond,
-		Role:       roleFor(a.isPublic, a.vpnIP, p.IsPublic(), vpnIP),
-		SignPubKey: p.SignPubKey,
-	}
-
-	a.peersByKey[p.WGPubKey] = peer
-	a.peersByIP[peer.VPNIP] = peer
-	defer a.updateHosts()
-
-	if !peer.IsPublic {
-		if a.isPublic {
-			// Public nodes accept traffic from non-public peers as soon as they
-			// initiate a handshake. Set /32 AllowedIPs now; WireGuard learns the
-			// endpoint from the incoming handshake automatically.
-			a.devPromote(peer)
-		} else {
-			a.devAddPeer(peer)
-		}
-		return
-	}
-
-	a.devAddDirect(peer, peer.PreferredEndpoint())
-}
-
-func (a *App) onRemovePeer(key wgtypes.Key) {
-	peer, exists := a.peersByKey[key]
-	if !exists {
-		return
-	}
-	a.devRemove(peer)
-	delete(a.peersByKey, key)
-	delete(a.peersByIP, peer.VPNIP)
-	a.updateHosts()
-
-	if peer == a.relay {
-		a.relay = nil
-		a.switchActiveRelay()
-	}
-}
-
-// switchActiveRelay promotes the lowest-latency relay peer to active.
-func (a *App) switchActiveRelay() {
-	if a.relay != nil {
-		// If we have a relay, it's public, so should go back to being a direct
-		// peer - this will convert it's /24 to a /32.
-		a.devAddDirect(a.relay, a.relay.PreferredEndpoint())
-		a.relay = nil
-	}
-
-	var best *Peer
-	for _, p := range a.peersByKey {
-		if !p.CanRelay() {
-			continue
-		}
-
-		if best == nil || p.RTT < best.RTT {
-			best = p
-		}
-	}
-	if best == nil {
-		log.Printf("no relay available")
-		return
-	}
-
-	a.devSetRelay(best, best.PreferredEndpoint())
-	a.relay = best
-}
-
-func preferredEndpoint(v4, v6 netip.AddrPort) netip.AddrPort {
-	// We always prefer v4 since all peers can connect to IPv4 addresses.
-	if v4.IsValid() {
-		return v4
-	}
-	return v6
-}
-
-func roleFor(selfIsPublic bool, selfIP netip.Addr, peerIsPublic bool, peerVPNIP netip.Addr) control.Role {
-	if !selfIsPublic && peerIsPublic {
-		return control.Client
-	}
-	if selfIsPublic && !peerIsPublic {
-		return control.Server
-	}
-	return control.RoleFor(selfIP, peerVPNIP)
-}

peer/on_hub_test.go

@@ -1,299 +0,0 @@
-package peer
-
-import (
-	"net/netip"
-	"testing"
-	"time"
-
-	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
-
-	"vppn/m"
-)
-
-func mustKey(t *testing.T) wgtypes.Key {
-	t.Helper()
-	k, err := wgtypes.GeneratePrivateKey()
-	if err != nil {
-		t.Fatalf("generate key: %v", err)
-	}
-	return k.PublicKey()
-}
-
-func TestOnAddPeer(t *testing.T) {
-	ep1 := netip.MustParseAddrPort("1.2.3.4:51820")
-	ep2 := netip.MustParseAddrPort("5.6.7.8:51820")
-	peerVPNIP := netip.MustParseAddr("10.0.0.2")
-
-	testCases := []struct {
-		name  string
-		setup func(a *App, key wgtypes.Key)
-		peer  func(key wgtypes.Key) m.Peer
-		check func(t *testing.T, a *App, dev *fakeWGDevice, key wgtypes.Key)
-	}{
-		{
-			name: "non-public peer registered in WG via AddPeer",
-			peer: func(k wgtypes.Key) m.Peer {
-				return m.Peer{WGPubKey: k, PeerIP: 2}
-			},
-			check: func(t *testing.T, a *App, dev *fakeWGDevice, key wgtypes.Key) {
-				p := a.peersByKey[key]
-				if p == nil {
-					t.Fatal("not in peersByKey")
-				}
-				if a.peersByIP[peerVPNIP] == nil {
-					t.Fatal("not in peersByIP")
-				}
-				if p.State != StateRelayed {
-					t.Fatalf("state = %v, want StateRelayed", p.State)
-				}
-				dev.AssertAddPeer(t, 0, key)
-			},
-		},
-		{
-			name: "public peer with endpoint registered via AddDirect",
-			peer: func(k wgtypes.Key) m.Peer {
-				return m.Peer{WGPubKey: k, PeerIP: 2, Addr4: ep1.Addr(), Port: ep1.Port()}
-			},
-			check: func(t *testing.T, a *App, dev *fakeWGDevice, key wgtypes.Key) {
-				p := a.peersByKey[key]
-				if p == nil {
-					t.Fatal("not in peersByKey")
-				}
-				dev.AssertAddDirect(t, 0, p.PubKey(), ep1, p.VPNIP)
-			},
-		},
-		{
-			name: "re-add removes old WG entry before adding new one",
-			setup: func(a *App, key wgtypes.Key) {
-				a.onAddPeer(m.Peer{WGPubKey: key, PeerIP: 2, Addr4: ep1.Addr(), Port: ep1.Port()})
-			},
-			peer: func(k wgtypes.Key) m.Peer {
-				return m.Peer{WGPubKey: k, PeerIP: 2, Addr4: ep2.Addr(), Port: ep2.Port()}
-			},
-			check: func(t *testing.T, a *App, dev *fakeWGDevice, key wgtypes.Key) {
-				if len(dev.Calls) != 2 {
-					t.Fatalf("dev calls = %v, want [RemovePeer, AddDirect]", dev.Calls)
-				}
-				dev.AssertRemovePeer(t, 0, key)
-				dev.AssertAddDirect(t, 1, key, ep2, peerVPNIP)
-				if len(a.peersByKey) != 1 || len(a.peersByIP) != 1 {
-					t.Errorf("maps: peersByKey=%d peersByIP=%d, want 1 each", len(a.peersByKey), len(a.peersByIP))
-				}
-			},
-		},
-	}
-
-	for _, tc := range testCases {
-		t.Run(tc.name, func(t *testing.T) {
-			a, dev, _ := newTestApp(t, "10.0.0.1", false, false)
-			key := mustKey(t)
-			if tc.setup != nil {
-				tc.setup(a, key)
-				dev.Calls = nil
-			}
-			a.onAddPeer(tc.peer(key))
-			tc.check(t, a, dev, key)
-		})
-	}
-}
-
-func TestOnRemovePeer(t *testing.T) {
-	ep1 := netip.MustParseAddrPort("1.2.3.4:51820")
-	ep2 := netip.MustParseAddrPort("5.6.7.8:51820")
-
-	testCases := []struct {
-		name  string
-		setup func(t *testing.T, a *App) wgtypes.Key // returns the key to remove
-		check func(t *testing.T, a *App, dev *fakeWGDevice)
-	}{
-		{
-			name: "unknown key is a no-op",
-			setup: func(t *testing.T, a *App) wgtypes.Key {
-				return mustKey(t)
-			},
-			check: func(t *testing.T, a *App, dev *fakeWGDevice) {
-				dev.AssertNoCalls(t)
-				if len(a.peersByKey) != 0 {
-					t.Errorf("peersByKey should be empty")
-				}
-			},
-		},
-		{
-			name: "StateRelayed peer removed from maps with RemovePeer",
-			setup: func(t *testing.T, a *App) wgtypes.Key {
-				key := mustKey(t)
-				a.onAddPeer(m.Peer{WGPubKey: key, PeerIP: 2})
-				return key
-			},
-			check: func(t *testing.T, a *App, dev *fakeWGDevice) {
-				if len(dev.Calls) != 1 {
-					t.Fatalf("dev calls = %v, want [RemovePeer]", dev.Calls)
-				}
-				dev.AssertRemovePeer(t, 0, dev.Calls[0].PubKey)
-				if len(a.peersByKey) != 0 || len(a.peersByIP) != 0 {
-					t.Errorf("maps should be empty after remove")
-				}
-			},
-		},
-		{
-			name: "StateDirect peer removed from maps with RemovePeer",
-			setup: func(t *testing.T, a *App) wgtypes.Key {
-				key := mustKey(t)
-				a.onAddPeer(m.Peer{WGPubKey: key, PeerIP: 2, Addr4: ep1.Addr(), Port: ep1.Port()})
-				return key
-			},
-			check: func(t *testing.T, a *App, dev *fakeWGDevice) {
-				if len(dev.Calls) != 1 {
-					t.Fatalf("dev calls = %v, want [RemovePeer]", dev.Calls)
-				}
-				dev.AssertRemovePeer(t, 0, dev.Calls[0].PubKey)
-				if len(a.peersByKey) != 0 || len(a.peersByIP) != 0 {
-					t.Errorf("maps should be empty after remove")
-				}
-			},
-		},
-		{
-			name: "removing active relay with no backup clears relay field",
-			setup: func(t *testing.T, a *App) wgtypes.Key {
-				relay := addRelayPeer(t, a, "10.0.0.10", ep1)
-				a.relay = relay
-				return relay.PubKey()
-			},
-			check: func(t *testing.T, a *App, dev *fakeWGDevice) {
-				if len(dev.Calls) != 1 {
-					t.Fatalf("dev calls = %v, want [RemovePeer]", dev.Calls)
-				}
-				dev.AssertRemovePeer(t, 0, dev.Calls[0].PubKey)
-				if a.relay != nil {
-					t.Errorf("relay should be nil after removing only relay")
-				}
-			},
-		},
-		{
-			name: "removing active relay elects backup via SetRelay",
-			setup: func(t *testing.T, a *App) wgtypes.Key {
-				relay1 := addRelayPeer(t, a, "10.0.0.10", ep1)
-				addRelayPeer(t, a, "10.0.0.11", ep2)
-				a.relay = relay1
-				return relay1.PubKey()
-			},
-			check: func(t *testing.T, a *App, dev *fakeWGDevice) {
-				if len(dev.Calls) != 2 {
-					t.Fatalf("dev calls = %v, want [RemovePeer, SetRelay]", dev.Calls)
-				}
-				dev.AssertRemovePeer(t, 0, dev.Calls[0].PubKey)
-				dev.AssertSetRelay(t, 1, dev.Calls[1].PubKey, ep2, a.vpnNet)
-				if a.relay == nil {
-					t.Errorf("relay should be set to backup after failover")
-				}
-			},
-		},
-	}
-
-	for _, tc := range testCases {
-		t.Run(tc.name, func(t *testing.T) {
-			a, dev, _ := newTestApp(t, "10.0.0.1", false, false)
-			key := tc.setup(t, a)
-			dev.Calls = nil
-			a.onRemovePeer(key)
-			tc.check(t, a, dev)
-		})
-	}
-}
-
-func TestSwitchActiveRelay(t *testing.T) {
-	ep1 := netip.MustParseAddrPort("1.2.3.4:51820")
-	ep2 := netip.MustParseAddrPort("5.6.7.8:51820")
-
-	testCases := []struct {
-		name  string
-		setup func(t *testing.T, a *App)
-		check func(t *testing.T, a *App, dev *fakeWGDevice)
-	}{
-		{
-			name:  "no candidates leaves relay nil",
-			setup: func(t *testing.T, a *App) {},
-			check: func(t *testing.T, a *App, dev *fakeWGDevice) {
-				dev.AssertNoCalls(t)
-				if a.relay != nil {
-					t.Error("relay should be nil")
-				}
-			},
-		},
-		{
-			name: "single candidate elected via SetRelay",
-			setup: func(t *testing.T, a *App) {
-				addRelayPeer(t, a, "10.0.0.10", ep1)
-			},
-			check: func(t *testing.T, a *App, dev *fakeWGDevice) {
-				if len(dev.Calls) != 1 {
-					t.Fatalf("dev calls = %v, want [SetRelay]", dev.Calls)
-				}
-				dev.AssertSetRelay(t, 0, dev.Calls[0].PubKey, ep1, a.vpnNet)
-				if a.relay == nil {
-					t.Error("relay should be set")
-				}
-			},
-		},
-		{
-			name: "measured RTT beats zero RTT",
-			setup: func(t *testing.T, a *App) {
-				r1 := addRelayPeer(t, a, "10.0.0.10", ep1)
-				r1.RTT = 10 * time.Millisecond
-				addRelayPeer(t, a, "10.0.0.11", ep2) // RTT stays MaxInt64 (unmeaured)
-			},
-			check: func(t *testing.T, a *App, dev *fakeWGDevice) {
-				if len(dev.Calls) != 1 {
-					t.Fatalf("dev calls = %v, want [SetRelay]", dev.Calls)
-				}
-				dev.AssertSetRelay(t, 0, dev.Calls[0].PubKey, ep1, a.vpnNet)
-			},
-		},
-		{
-			name: "lower RTT wins",
-			setup: func(t *testing.T, a *App) {
-				r1 := addRelayPeer(t, a, "10.0.0.10", ep1)
-				r1.RTT = 5 * time.Millisecond
-				r2 := addRelayPeer(t, a, "10.0.0.11", ep2)
-				r2.RTT = 20 * time.Millisecond
-			},
-			check: func(t *testing.T, a *App, dev *fakeWGDevice) {
-				if len(dev.Calls) != 1 {
-					t.Fatalf("dev calls = %v, want [SetRelay]", dev.Calls)
-				}
-				dev.AssertSetRelay(t, 0, dev.Calls[0].PubKey, ep1, a.vpnNet)
-			},
-		},
-		{
-			name: "stale relay demoted to direct before backup elected",
-			setup: func(t *testing.T, a *App) {
-				old := addRelayPeer(t, a, "10.0.0.10", ep1)
-				old.wgPeer.LastHandshakeTime = time.Time{} // stale — triggers switch from onTick
-				a.relay = old
-				addRelayPeer(t, a, "10.0.0.11", ep2)
-			},
-			check: func(t *testing.T, a *App, dev *fakeWGDevice) {
-				if len(dev.Calls) != 2 {
-					t.Fatalf("dev calls = %v, want [AddDirect, SetRelay]", dev.Calls)
-				}
-				if dev.Calls[0].Method != "AddDirect" || dev.Calls[0].Endpoint != ep1 {
-					t.Errorf("call[0]: got %v, want AddDirect with ep1", dev.Calls[0])
-				}
-				dev.AssertSetRelay(t, 1, dev.Calls[1].PubKey, ep2, a.vpnNet)
-				if a.relay == nil || a.relay.EndpointV4 != ep2 {
-					t.Error("relay should be the backup peer")
-				}
-			},
-		},
-	}
-
-	for _, tc := range testCases {
-		t.Run(tc.name, func(t *testing.T) {
-			a, dev, _ := newTestApp(t, "10.0.0.1", false, false)
-			tc.setup(t, a)
-			dev.Calls = nil
-			a.switchActiveRelay()
-			tc.check(t, a, dev)
-		})
-	}
-}

peer/on_multicast.go

@@ -1,51 +0,0 @@
-package peer
-
-import (
-	"net/netip"
-
-	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
-
-	"vppn/peer/multicast"
-)
-
-func (a *App) onMulticastDiscovery(pkt multicast.Packet) {
-	if a.isPublic {
-		return
-	}
-
-	// Locate the sender peer by its VPN IP (final octet carried in the beacon).
-	octets := a.vpnNet.Addr().As4()
-	octets[3] = pkt.PeerIP
-	vpnIP := netip.AddrFrom4(octets)
-
-	peer, ok := a.peersByIP[vpnIP]
-	if !ok || peer.IsPublic || peer.State == StateDirect {
-		return
-	}
-
-	// Authenticate the beacon against the peer's known sign key. scratch[:0]
-	// gives sign.Open an empty-but-capacity buffer to decode into.
-	if !pkt.Verify(a.scratch[:0], &peer.SignPubKey) {
-		return
-	}
-
-	// The beacon is authentic but must also advertise the WG key the hub gave
-	// us for this peer; otherwise it's inconsistent — drop it.
-	if wgtypes.Key(pkt.WGPubKey) != peer.PubKey() {
-		return
-	}
-
-	endpoint := netip.AddrPortFrom(pkt.Src, pkt.WGPort)
-	if !endpoint.IsValid() {
-		return
-	}
-
-	var v4, v6 netip.AddrPort
-	if pkt.Src.Is4() {
-		v4 = endpoint
-	} else {
-		v6 = endpoint
-	}
-
-	a.addProbe(peer, v4, v6)
-}

peer/on_ping.go

@@ -1,58 +0,0 @@
-package peer
-
-import (
-	"net/netip"
-	"time"
-
-	"vppn/peer/control"
-)
-
-func (a *App) onPing(e PingEvent) {
-	peer, ok := a.peersByIP[e.srcVPNIP]
-	if !ok {
-		// TODO: Log here.
-		return
-	}
-
-	now := time.Now()
-
-	// If we're the server, respond - this is always necessary as it's used to
-	// know if peers are up or down.
-	if peer.Role == control.Server {
-		a.sendPing(peer, e.ping.PingTS)
-	}
-
-	// Compute RTT from server echo.
-	if peer.Role == control.Client {
-		peer.RTT = now.Sub(time.Unix(0, e.ping.PingTS))
-	}
-
-	// If we're public, nothing more to do.
-	if a.isPublic {
-		return
-	}
-
-	// We can only learn our own endpoint from directly-connected peers — Dst
-	// is the sender's observation of our WG handshake source.
-	if peer.State == StateDirect {
-		if dst := e.ping.Dst; dst.IsValid() {
-			if dst.Addr().Is4() {
-				a.selfV4 = dst
-			} else {
-				a.selfV6 = dst
-			}
-		}
-		return
-	}
-
-	a.addProbe(peer, e.ping.SrcV4, e.ping.SrcV6)
-}
-
-func (a *App) addProbe(peer *Peer, v4, v6 netip.AddrPort) {
-	endpoint := preferredEndpoint(v4, v6)
-	if !endpoint.IsValid() || endpoint == peer.PreferredEndpoint() {
-		return
-	}
-	peer.UpdateEndpoints(v4, v6)
-	a.devAddProbe(peer, endpoint)
-}

peer/on_tick.go

@@ -1,52 +0,0 @@
-package peer
-
-import (
-	"log"
-	"time"
-
-	"vppn/peer/control"
-	"vppn/peer/wginterface"
-)
-
-func (a *App) onTick() {
-	wgPeers := a.devPeers()
-
-	now := time.Now().UnixNano()
-
-	for _, wgPeer := range wgPeers {
-		p, ok := a.peersByKey[wgPeer.PublicKey]
-		if !ok {
-			log.Printf("Wireguard peer not in index, removing: %v", wgPeer)
-			a.devRemove(&Peer{wgPeer: wgPeer})
-			continue
-		}
-		p.wgPeer = wgPeer
-
-		// Send pings to peers where we're the client.
-		if p.Role == control.Client {
-			a.sendPing(p, now)
-		}
-
-		switch p.State {
-		case StateProbing:
-			// Promote probing peers to direct once alive (direct path confirmed
-			// working).
-			if time.Since(p.LastHandshakeTime()) < 2*wginterface.ProbeKeepalive {
-				a.devPromote(p)
-			}
-
-		case StateDirect:
-			if p.IsPublic || a.isPublic || p.Up() {
-				break
-			}
-			// Stale non-public direct peer: demote to probing so WireGuard
-			// resumes handshake attempts on the direct path.
-			a.devAddProbe(p, p.WGEndpoint())
-		}
-	}
-
-	// Ensure we have a live relay (if we're not public).
-	if !a.isPublic && (a.relay == nil || !a.relay.Up()) {
-		a.switchActiveRelay()
-	}
-}

peer/packets-util.go

@@ -0,0 +1,182 @@
+package peer
+
+import (
+	"net/netip"
+	"unsafe"
+)
+
+// ----------------------------------------------------------------------------
+
+type binWriter struct {
+	b []byte
+	i int
+}
+
+func newBinWriter(buf []byte) *binWriter {
+	buf = buf[:cap(buf)]
+	return &binWriter{buf, 0}
+}
+
+func (w *binWriter) Bool(b bool) *binWriter {
+	if b {
+		return w.Byte(1)
+	}
+	return w.Byte(0)
+}
+
+func (w *binWriter) Byte(b byte) *binWriter {
+	w.b[w.i] = b
+	w.i++
+	return w
+}
+
+func (w *binWriter) SharedKey(key [32]byte) *binWriter {
+	copy(w.b[w.i:w.i+32], key[:])
+	w.i += 32
+	return w
+}
+
+func (w *binWriter) Uint16(x uint16) *binWriter {
+	*(*uint16)(unsafe.Pointer(&w.b[w.i])) = x
+	w.i += 2
+	return w
+}
+
+func (w *binWriter) Uint64(x uint64) *binWriter {
+	*(*uint64)(unsafe.Pointer(&w.b[w.i])) = x
+	w.i += 8
+	return w
+}
+
+func (w *binWriter) Int64(x int64) *binWriter {
+	*(*int64)(unsafe.Pointer(&w.b[w.i])) = x
+	w.i += 8
+	return w
+}
+
+func (w *binWriter) AddrPort(addrPort netip.AddrPort) *binWriter {
+	w.Bool(addrPort.IsValid())
+	addr := addrPort.Addr().As16()
+	copy(w.b[w.i:w.i+16], addr[:])
+	w.i += 16
+	return w.Uint16(addrPort.Port())
+}
+
+func (w *binWriter) AddrPort8(l [8]netip.AddrPort) *binWriter {
+	for _, addrPort := range l {
+		w.AddrPort(addrPort)
+	}
+	return w
+}
+
+func (w *binWriter) Build() []byte {
+	return w.b[:w.i]
+}
+
+// ----------------------------------------------------------------------------
+
+type binReader struct {
+	b   []byte
+	i   int
+	err error
+}
+
+func newBinReader(buf []byte) *binReader {
+	return &binReader{b: buf}
+}
+
+func (r *binReader) hasBytes(n int) bool {
+	if r.err != nil || (len(r.b)-r.i) < n {
+		r.err = errMalformedPacket
+		return false
+	}
+	return true
+}
+
+func (r *binReader) Bool(b *bool) *binReader {
+	var bb byte
+	r.Byte(&bb)
+	*b = bb != 0
+	return r
+}
+
+func (r *binReader) Byte(b *byte) *binReader {
+	if !r.hasBytes(1) {
+		return r
+	}
+	*b = r.b[r.i]
+	r.i++
+	return r
+}
+
+func (r *binReader) SharedKey(x *[32]byte) *binReader {
+	if !r.hasBytes(32) {
+		return r
+	}
+	*x = ([32]byte)(r.b[r.i : r.i+32])
+	r.i += 32
+	return r
+}
+
+func (r *binReader) Uint16(x *uint16) *binReader {
+	if !r.hasBytes(2) {
+		return r
+	}
+	*x = *(*uint16)(unsafe.Pointer(&r.b[r.i]))
+	r.i += 2
+	return r
+}
+
+func (r *binReader) Uint64(x *uint64) *binReader {
+	if !r.hasBytes(8) {
+		return r
+	}
+	*x = *(*uint64)(unsafe.Pointer(&r.b[r.i]))
+	r.i += 8
+	return r
+}
+
+func (r *binReader) Int64(x *int64) *binReader {
+	if !r.hasBytes(8) {
+		return r
+	}
+	*x = *(*int64)(unsafe.Pointer(&r.b[r.i]))
+	r.i += 8
+	return r
+}
+
+func (r *binReader) AddrPort(x *netip.AddrPort) *binReader {
+	if !r.hasBytes(19) {
+		return r
+	}
+
+	var (
+		valid bool
+		port  uint16
+	)
+
+	r.Bool(&valid)
+	addr := netip.AddrFrom16(([16]byte)(r.b[r.i : r.i+16])).Unmap()
+	r.i += 16
+
+	r.Uint16(&port)
+
+	if valid {
+		*x = netip.AddrPortFrom(addr, port)
+	} else {
+		*x = netip.AddrPort{}
+	}
+
+	return r
+}
+
+func (r *binReader) AddrPort8(x *[8]netip.AddrPort) *binReader {
+	for i := range x {
+		r.AddrPort(&x[i])
+	}
+	return r
+}
+
+func (r *binReader) Error() error {
+	return r.err
+}

peer/packets-util_test.go

@@ -0,0 +1,76 @@
+package peer
+
+import (
+	"net/netip"
+	"reflect"
+	"testing"
+)
+
+func TestBinWriteRead_invalidAddrPort(t *testing.T) {
+	addr := netip.AddrPort{}
+	buf := make([]byte, 1024)
+	buf = newBinWriter(buf).
+		AddrPort(addr).
+		Build()
+
+	var addr2 netip.AddrPort
+	err := newBinReader(buf).
+		AddrPort(&addr2).
+		Error()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if addr2.IsValid() {
+		t.Fatal(addr, addr2)
+	}
+}
+
+func TestBinWriteRead(t *testing.T) {
+	buf := make([]byte, 1024)
+
+	type Item struct {
+		Type     byte
+		TraceID  uint64
+		Addrs    [8]netip.AddrPort
+		DestAddr netip.AddrPort
+	}
+
+	in := Item{
+		1,
+		2,
+		[8]netip.AddrPort{},
+		netip.AddrPortFrom(netip.AddrFrom4([4]byte{1, 2, 3, 4}), 22),
+	}
+
+	in.Addrs[0] = netip.AddrPortFrom(netip.AddrFrom4([4]byte{0, 1, 2, 3}), 20)
+	in.Addrs[2] = netip.AddrPortFrom(netip.AddrFrom4([4]byte{2, 3, 4, 5}), 22)
+	in.Addrs[3] = netip.AddrPortFrom(netip.AddrFrom4([4]byte{2, 3, 4, 3}), 23)
+	in.Addrs[4] = netip.AddrPortFrom(netip.AddrFrom4([4]byte{2, 3, 4, 4}), 24)
+	in.Addrs[5] = netip.AddrPortFrom(netip.AddrFrom4([4]byte{2, 3, 4, 5}), 25)
+	in.Addrs[6] = netip.AddrPortFrom(netip.AddrFrom4([4]byte{2, 3, 4, 6}), 26)
+	in.Addrs[7] = netip.AddrPortFrom(netip.AddrFrom4([4]byte{7, 8, 9, 7}), 27)
+
+	buf = newBinWriter(buf).
+		Byte(in.Type).
+		Uint64(in.TraceID).
+		AddrPort(in.DestAddr).
+		AddrPort8(in.Addrs).
+		Build()
+
+	out := Item{}
+
+	err := newBinReader(buf).
+		Byte(&out.Type).
+		Uint64(&out.TraceID).
+		AddrPort(&out.DestAddr).
+		AddrPort8(&out.Addrs).
+		Error()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if !reflect.DeepEqual(in, out) {
+		t.Fatal(in, out)
+	}
+}

peer/packets.go

@@ -0,0 +1,120 @@
+package peer
+
+import (
+	"net/netip"
+)
+
+const (
+	packetTypeSyn           = 1
+	packetTypeInit          = 2
+	packetTypeAck           = 3
+	packetTypeProbe         = 4
+	packetTypeAddrDiscovery = 5
+)
+
+// ----------------------------------------------------------------------------
+
+type packetInit struct {
+	TraceID uint64
+	Direct  bool
+	Version uint64
+}
+
+func (p packetInit) Marshal(buf []byte) []byte {
+	return newBinWriter(buf).
+		Byte(packetTypeInit).
+		Uint64(p.TraceID).
+		Bool(p.Direct).
+		Uint64(p.Version).
+		Build()
+}
+
+func parsePacketInit(buf []byte) (p packetInit, err error) {
+	err = newBinReader(buf[1:]).
+		Uint64(&p.TraceID).
+		Bool(&p.Direct).
+		Uint64(&p.Version).
+		Error()
+	return
+}
+
+// ----------------------------------------------------------------------------
+
+type packetSyn struct {
+	TraceID       uint64   // TraceID to match response w/ request.
+	SharedKey     [32]byte // Our shared key.
+	Direct        bool
+	PossibleAddrs [8]netip.AddrPort // Possible public addresses of the sender.
+}
+
+func (p packetSyn) Marshal(buf []byte) []byte {
+	return newBinWriter(buf).
+		Byte(packetTypeSyn).
+		Uint64(p.TraceID).
+		SharedKey(p.SharedKey).
+		Bool(p.Direct).
+		AddrPort8(p.PossibleAddrs).
+		Build()
+}
+
+func parsePacketSyn(buf []byte) (p packetSyn, err error) {
+	err = newBinReader(buf[1:]).
+		Uint64(&p.TraceID).
+		SharedKey(&p.SharedKey).
+		Bool(&p.Direct).
+		AddrPort8(&p.PossibleAddrs).
+		Error()
+	return
+}
+
+// ----------------------------------------------------------------------------
+
+type packetAck struct {
+	TraceID       uint64
+	ToAddr        netip.AddrPort
+	PossibleAddrs [8]netip.AddrPort // Possible public addresses of the sender.
+}
+
+func (p packetAck) Marshal(buf []byte) []byte {
+	return newBinWriter(buf).
+		Byte(packetTypeAck).
+		Uint64(p.TraceID).
+		AddrPort(p.ToAddr).
+		AddrPort8(p.PossibleAddrs).
+		Build()
+}
+
+func parsePacketAck(buf []byte) (p packetAck, err error) {
+	err = newBinReader(buf[1:]).
+		Uint64(&p.TraceID).
+		AddrPort(&p.ToAddr).
+		AddrPort8(&p.PossibleAddrs).
+		Error()
+	return
+}
+
+// ----------------------------------------------------------------------------
+
+// A probeReqPacket is sent from a client to a server to determine if direct
+// UDP communication can be used.
+type packetProbe struct {
+	TraceID uint64
+}
+
+func (p packetProbe) Marshal(buf []byte) []byte {
+	return newBinWriter(buf).
+		Byte(packetTypeProbe).
+		Uint64(p.TraceID).
+		Build()
+}
+
+func parsePacketProbe(buf []byte) (p packetProbe, err error) {
+	err = newBinReader(buf[1:]).
+		Uint64(&p.TraceID).
+		Error()
+	return
+}
+
+// ----------------------------------------------------------------------------
+
+type packetLocalDiscovery struct{}

peer/packets_test.go

@@ -0,0 +1,64 @@
+package peer
+
+import (
+	"crypto/rand"
+	"net/netip"
+	"reflect"
+	"testing"
+)
+
+func TestSynPacket(t *testing.T) {
+	p := packetSyn{
+		TraceID: 2342342345,
+		Direct:  true,
+	}
+	rand.Read(p.SharedKey[:])
+
+	p.PossibleAddrs[0] = netip.AddrPortFrom(netip.AddrFrom4([4]byte{1, 2, 3, 4}), 234)
+	p.PossibleAddrs[1] = netip.AddrPortFrom(netip.AddrFrom4([4]byte{2, 2, 3, 4}), 12399)
+	p.PossibleAddrs[2] = netip.AddrPortFrom(netip.AddrFrom4([4]byte{3, 2, 3, 4}), 60000)
+
+	buf := p.Marshal(newBuf())
+	p2, err := parsePacketSyn(buf)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(p, p2) {
+		t.Fatal(p2)
+	}
+}
+
+func TestAckPacket(t *testing.T) {
+	p := packetAck{
+		TraceID: 123213,
+		ToAddr:  netip.AddrPortFrom(netip.AddrFrom4([4]byte{1, 2, 3, 4}), 234),
+	}
+
+	p.PossibleAddrs[0] = netip.AddrPortFrom(netip.AddrFrom4([4]byte{8, 2, 3, 4}), 100)
+	p.PossibleAddrs[1] = netip.AddrPortFrom(netip.AddrFrom4([4]byte{2, 2, 3, 4}), 12399)
+	p.PossibleAddrs[2] = netip.AddrPortFrom(netip.AddrFrom4([4]byte{3, 2, 3, 4}), 60000)
+
+	buf := p.Marshal(newBuf())
+	p2, err := parsePacketAck(buf)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(p, p2) {
+		t.Fatal(p2)
+	}
+}
+
+func TestProbePacket(t *testing.T) {
+	p := packetProbe{
+		TraceID: 12345,
+	}
+
+	buf := p.Marshal(newBuf())
+	p2, err := parsePacketProbe(buf)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(p, p2) {
+		t.Fatal(p2)
+	}
+}

peer/peer.go

@@ -0,0 +1,197 @@
+package peer
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"log"
+	"math"
+	"net"
+	"net/http"
+	"net/netip"
+	"net/url"
+	"os"
+	"vppn/m"
+
+	"git.crumpington.com/lib/go/flock"
+)
+
+type peerMain struct {
+	Globals
+	ifReader   *IFReader
+	connReader *ConnReader
+	hubPoller  *HubPoller
+	lockFile   *os.File
+}
+
+func newPeerMain(args mainArgs) *peerMain {
+	logf := func(s string, args ...any) {
+		log.Printf("[Main] "+s, args...)
+	}
+
+	lockFile, err := flock.TryLock(lockFilePath(args.NetName))
+	if err != nil {
+		log.Fatalf("Failed to open lock file: %v", err)
+	}
+	if lockFile == nil {
+		log.Fatalf("Failed to obtain file lock.")
+	}
+
+	config, err := loadPeerConfig(args.NetName)
+	if err != nil {
+		logf("Failed to load configuration: %v", err)
+		logf("Initializing...")
+		initPeerWithHub(args)
+
+		config, err = loadPeerConfig(args.NetName)
+		if err != nil {
+			log.Fatalf("Failed to load configuration: %v", err)
+		}
+	}
+
+	state, err := loadNetworkState(args.NetName)
+	if err != nil {
+		log.Fatalf("Failed to load network state: %v", err)
+	}
+
+	startupCount, err := loadStartupCount(args.NetName)
+	if err != nil {
+		if !os.IsNotExist(err) {
+			log.Fatalf("Failed to load startup count: %v", err)
+		}
+	}
+
+	if startupCount.Count == math.MaxUint16 {
+		log.Fatalf("Startup counter overflow.")
+	}
+	startupCount.Count += 1
+
+	if err := storeStartupCount(args.NetName, startupCount); err != nil {
+		log.Fatalf("Failed to write startup count: %v", err)
+	}
+
+	iface, err := openInterface(config.Network, config.LocalPeerIP, args.NetName)
+	if err != nil {
+		log.Fatalf("Failed to open interface: %v", err)
+	}
+
+	localPeer := state.Peers[config.LocalPeerIP]
+
+	myAddr, err := net.ResolveUDPAddr("udp", fmt.Sprintf(":%d", localPeer.Port))
+	if err != nil {
+		log.Fatalf("Failed to resolve UDP address: %v", err)
+	}
+
+	logf("Listening on %v...", myAddr)
+	conn, err := net.ListenUDP("udp", myAddr)
+	if err != nil {
+		log.Fatalf("Failed to open UDP port: %v", err)
+	}
+
+	conn.SetReadBuffer(1024 * 1024 * 8)
+	conn.SetWriteBuffer(1024 * 1024 * 8)
+
+	var localAddr netip.AddrPort
+	ip, localAddrValid := netip.AddrFromSlice(localPeer.PublicIP)
+	if localAddrValid {
+		localAddr = netip.AddrPortFrom(ip, localPeer.Port)
+	}
+
+	g := NewGlobals(config, startupCount, localAddr, conn, iface)
+
+	hubPoller, err := NewHubPoller(g, args.NetName, args.HubAddress, args.APIKey)
+	if err != nil {
+		log.Fatalf("Failed to create hub poller: %v", err)
+	}
+
+	// Start status server.
+	go runStatusServer(g, statusSocketPath(args.NetName))
+
+	return &peerMain{
+		Globals:    g,
+		ifReader:   NewIFReader(g),
+		connReader: NewConnReader(g, conn),
+		hubPoller:  hubPoller,
+		lockFile:   lockFile,
+	}
+}
+
+func (p *peerMain) Run() {
+	for i := range p.RemotePeers {
+		remote := p.RemotePeers[i].Load()
+		go newRemoteFSM(remote).Run()
+	}
+
+	go p.ifReader.Run()
+	go p.connReader.Run()
+
+	if !p.LocalAddrValid {
+		go RunMCWriter(p.LocalPeerIP, p.PrivSignKey)
+		go RunMCReader(p.Globals)
+	}
+
+	go p.hubPoller.Run()
+
+	select {}
+}
+
+func initPeerWithHub(args mainArgs) {
+	keys := generateKeys()
+
+	initURL, err := url.Parse(args.HubAddress)
+	if err != nil {
+		log.Fatalf("Failed to parse hub URL: %v", err)
+	}
+	initURL.Path = "/peer/init/"
+
+	initArgs := m.PeerInitArgs{
+		EncPubKey:  keys.PubKey,
+		PubSignKey: keys.PubSignKey,
+	}
+
+	buf := &bytes.Buffer{}
+	if err := json.NewEncoder(buf).Encode(initArgs); err != nil {
+		log.Fatalf("Failed to encode init args: %v", err)
+	}
+
+	req, err := http.NewRequest(http.MethodPost, initURL.String(), buf)
+	if err != nil {
+		log.Fatalf("Failed to construct request: %v", err)
+	}
+	req.SetBasicAuth("", args.APIKey)
+
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		log.Fatalf("Failed to init with hub: %v", err)
+	}
+	defer resp.Body.Close()
+
+	data, err := io.ReadAll(resp.Body)
+	if err != nil {
+		log.Fatalf("Failed to read response body: %v", err)
+	}
+
+	initResp := m.PeerInitResp{}
+	if err := json.Unmarshal(data, &initResp); err != nil {
+		log.Fatalf("Failed to parse configuration: %v\n%s", err, data)
+	}
+
+	config := LocalConfig{}
+	config.LocalPeerIP = initResp.PeerIP
+	config.Network = initResp.Network
+	config.PubKey = keys.PubKey
+	config.PrivKey = keys.PrivKey
+	config.PubSignKey = keys.PubSignKey
+	config.PrivSignKey = keys.PrivSignKey
+
+	if err := storeNetworkState(args.NetName, initResp.NetworkState); err != nil {
+		log.Fatalf("Failed to store network state: %v", err)
+	}
+
+	if err := storePeerConfig(args.NetName, config); err != nil {
+		log.Fatalf("Failed to store configuration: %v", err)
+	}
+
+	log.Print("Initialization successful.")
+}

peer/ping.go

@@ -1,21 +0,0 @@
-package peer
-
-import (
-	"log"
-	"net/netip"
-
-	"vppn/peer/control"
-)
-
-func (a *App) sendPing(p *Peer, ts int64) {
-	ping := control.Ping{
-		PingTS: ts,
-		SrcV4:  a.selfV4,
-		SrcV6:  a.selfV6,
-		Dst:    p.WGEndpoint(),
-	}
-	dst := netip.AddrPortFrom(p.VPNIP, ControlPort)
-	if err := a.controlConn.SendPing(dst, ping, a.scratch); err != nil {
-		log.Printf("sendPing %v: %v", p.VPNIP, err)
-	}
-}

peer/pubaddrs.go

@@ -0,0 +1,86 @@
+package peer
+
+import (
+	"net/netip"
+	"sort"
+	"sync"
+	"time"
+)
+
+type pubAddrStore struct {
+	lock      sync.Mutex
+	localPub  bool
+	localAddr netip.AddrPort
+	lastSeen  map[netip.AddrPort]time.Time
+	addrList  []netip.AddrPort
+}
+
+func newPubAddrStore(localAddr netip.AddrPort) *pubAddrStore {
+	return &pubAddrStore{
+		localPub:  localAddr.IsValid(),
+		localAddr: localAddr,
+		lastSeen:  map[netip.AddrPort]time.Time{},
+		addrList:  make([]netip.AddrPort, 0, 32),
+	}
+}
+
+func (store *pubAddrStore) Store(addr netip.AddrPort) {
+	if store.localPub {
+		return
+	}
+
+	if !addr.IsValid() {
+		return
+	}
+
+	if addr.Addr().IsPrivate() {
+		return
+	}
+
+	store.lock.Lock()
+	defer store.lock.Unlock()
+
+	if _, exists := store.lastSeen[addr]; !exists {
+		store.addrList = append(store.addrList, addr)
+	}
+	store.lastSeen[addr] = time.Now()
+	store.sort()
+}
+
+func (store *pubAddrStore) Get() (addrs [8]netip.AddrPort) {
+	store.lock.Lock()
+	defer store.lock.Unlock()
+
+	store.clean()
+
+	if store.localPub {
+		addrs[0] = store.localAddr
+		return
+	}
+
+	copy(addrs[:], store.addrList)
+	return
+}
+
+func (store *pubAddrStore) clean() {
+	if store.localPub {
+		return
+	}
+
+	for ip, lastSeen := range store.lastSeen {
+		if time.Since(lastSeen) > timeoutInterval {
+			delete(store.lastSeen, ip)
+		}
+	}
+	store.addrList = store.addrList[:0]
+	for ip := range store.lastSeen {
+		store.addrList = append(store.addrList, ip)
+	}
+	store.sort()
+}
+
+func (store *pubAddrStore) sort() {
+	sort.Slice(store.addrList, func(i, j int) bool {
+		return store.lastSeen[store.addrList[j]].Before(store.lastSeen[store.addrList[i]])
+	})
+}

peer/pubaddrs_test.go

@@ -0,0 +1,29 @@
+package peer
+
+import (
+	"net/netip"
+	"testing"
+	"time"
+)
+
+func TestPubAddrStore(t *testing.T) {
+	s := newPubAddrStore(netip.AddrPort{})
+
+	l := []netip.AddrPort{
+		netip.AddrPortFrom(netip.AddrFrom4([4]byte{0, 1, 2, 3}), 20),
+		netip.AddrPortFrom(netip.AddrFrom4([4]byte{1, 1, 2, 3}), 21),
+		netip.AddrPortFrom(netip.AddrFrom4([4]byte{2, 1, 2, 3}), 22),
+	}
+
+	for i := range l {
+		s.Store(l[i])
+		time.Sleep(time.Millisecond)
+	}
+
+	s.clean()
+
+	l2 := s.Get()
+	if l2[0] != l[2] || l2[1] != l[1] || l2[2] != l[0] {
+		t.Fatal(l, l2)
+	}
+}

peer/relayhandler.go

@@ -0,0 +1,54 @@
+package peer
+
+import (
+	"log"
+	"sync"
+	"sync/atomic"
+)
+
+type relayHandler struct {
+	lock   sync.Mutex
+	relays map[byte]*Remote
+	relay  atomic.Pointer[Remote]
+}
+
+func newRelayHandler() *relayHandler {
+	return &relayHandler{
+		relays: make(map[byte]*Remote, 256),
+	}
+}
+
+func (h *relayHandler) Add(r *Remote) {
+	h.lock.Lock()
+	defer h.lock.Unlock()
+
+	h.relays[r.RemotePeerIP] = r
+
+	if h.relay.Load() == nil {
+		log.Printf("Setting Relay: %v", r.conf().Peer.Name)
+		h.relay.Store(r)
+	}
+}
+
+func (h *relayHandler) Remove(r *Remote) {
+	h.lock.Lock()
+	defer h.lock.Unlock()
+
+	log.Printf("Removing relay %d...", r.RemotePeerIP)
+	delete(h.relays, r.RemotePeerIP)
+
+	if h.relay.Load() == r {
+		// Remove current relay.
+		h.relay.Store(nil)
+
+		// Find new relay.
+		for _, r := range h.relays {
+			h.relay.Store(r)
+			break
+		}
+	}
+}
+
+func (h *relayHandler) Load() *Remote {
+	return h.relay.Load()
+}