1 files changed, 70 insertions, 1 deletions
diff --git a/device/device_test.go b/device/device_test.go
index 8cffe08..fff172b 100644
--- a/device/device_test.go
+++ b/device/device_test.go
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2021 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
  */
 
 package device
@@ -12,6 +12,7 @@ import (
 	"io"
 	"math/rand"
 	"net/netip"
+	"os"
 	"runtime"
 	"runtime/pprof"
 	"sync"
@@ -21,6 +22,7 @@ import (
 
 	"golang.zx2c4.com/wireguard/conn"
 	"golang.zx2c4.com/wireguard/conn/bindtest"
+	"golang.zx2c4.com/wireguard/tun"
 	"golang.zx2c4.com/wireguard/tun/tuntest"
 )
 
@@ -307,6 +309,17 @@ func TestConcurrencySafety(t *testing.T) {
 		}
 	})
 
+	// Perform bind updates and keepalive sends concurrently with tunnel use.
+	t.Run("bindUpdate and keepalive", func(t *testing.T) {
+		const iters = 10
+		for i := 0; i < iters; i++ {
+			for _, peer := range pair {
+				peer.dev.BindUpdate()
+				peer.dev.SendKeepalivesToPeersWithCurrentKeypair()
+			}
+		}
+	})
+
 	close(done)
 }
 
@@ -405,3 +418,59 @@ func goroutineLeakCheck(t *testing.T) {
 		t.Fatalf("expected %d goroutines, got %d, leak?", startGoroutines, endGoroutines)
 	})
 }
+
+type fakeBindSized struct {
+	size int
+}
+
+func (b *fakeBindSized) Open(port uint16) (fns []conn.ReceiveFunc, actualPort uint16, err error) {
+	return nil, 0, nil
+}
+func (b *fakeBindSized) Close() error                                  { return nil }
+func (b *fakeBindSized) SetMark(mark uint32) error                     { return nil }
+func (b *fakeBindSized) Send(bufs [][]byte, ep conn.Endpoint) error    { return nil }
+func (b *fakeBindSized) ParseEndpoint(s string) (conn.Endpoint, error) { return nil, nil }
+func (b *fakeBindSized) BatchSize() int                                { return b.size }
+
+type fakeTUNDeviceSized struct {
+	size int
+}
+
+func (t *fakeTUNDeviceSized) File() *os.File { return nil }
+func (t *fakeTUNDeviceSized) Read(bufs [][]byte, sizes []int, offset int) (n int, err error) {
+	return 0, nil
+}
+func (t *fakeTUNDeviceSized) Write(bufs [][]byte, offset int) (int, error) { return 0, nil }
+func (t *fakeTUNDeviceSized) MTU() (int, error)                            { return 0, nil }
+func (t *fakeTUNDeviceSized) Name() (string, error)                        { return "", nil }
+func (t *fakeTUNDeviceSized) Events() <-chan tun.Event                     { return nil }
+func (t *fakeTUNDeviceSized) Close() error                                 { return nil }
+func (t *fakeTUNDeviceSized) BatchSize() int                               { return t.size }
+
+func TestBatchSize(t *testing.T) {
+	d := Device{}
+
+	d.net.bind = &fakeBindSized{1}
+	d.tun.device = &fakeTUNDeviceSized{1}
+	if want, got := 1, d.BatchSize(); got != want {
+		t.Errorf("expected batch size %d, got %d", want, got)
+	}
+
+	d.net.bind = &fakeBindSized{1}
+	d.tun.device = &fakeTUNDeviceSized{128}
+	if want, got := 128, d.BatchSize(); got != want {
+		t.Errorf("expected batch size %d, got %d", want, got)
+	}
+
+	d.net.bind = &fakeBindSized{128}
+	d.tun.device = &fakeTUNDeviceSized{1}
+	if want, got := 128, d.BatchSize(); got != want {
+		t.Errorf("expected batch size %d, got %d", want, got)
+	}
+
+	d.net.bind = &fakeBindSized{128}
+	d.tun.device = &fakeTUNDeviceSized{128}
+	if want, got := 128, d.BatchSize(); got != want {
+		t.Errorf("expected batch size %d, got %d", want, got)
+	}
+}