Move Linux client & common packages into a public repo.

derp/derp_test.go

@@ -0,0 +1,125 @@
+// Copyright (c) 2020 Tailscale Inc & AUTHORS All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package derp
+
+import (
+	"bufio"
+	"crypto/rand"
+	"net"
+	"testing"
+	"time"
+
+	"golang.org/x/crypto/curve25519"
+)
+
+func TestSendRecv(t *testing.T) {
+	const numClients = 3
+	var serverPrivateKey [32]byte
+	if _, err := rand.Read(serverPrivateKey[:]); err != nil {
+		t.Fatal(err)
+	}
+	var clientPrivateKeys [][32]byte
+	for i := 0; i < numClients; i++ {
+		var key [32]byte
+		if _, err := rand.Read(key[:]); err != nil {
+			t.Fatal(err)
+		}
+		clientPrivateKeys = append(clientPrivateKeys, key)
+	}
+	var clientKeys [][32]byte
+	for _, privKey := range clientPrivateKeys {
+		var key [32]byte
+		curve25519.ScalarBaseMult(&key, &privKey)
+		clientKeys = append(clientKeys, key)
+	}
+
+	ln, err := net.Listen("tcp", ":0")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var clientConns []net.Conn
+	for i := 0; i < numClients; i++ {
+		conn, err := net.Dial("tcp", ln.Addr().String())
+		if err != nil {
+			t.Fatal(err)
+		}
+		clientConns = append(clientConns, conn)
+	}
+	s := NewServer(serverPrivateKey, t.Logf)
+	defer s.Close()
+	for i := 0; i < numClients; i++ {
+		netConn, err := ln.Accept()
+		if err != nil {
+			t.Fatal(err)
+		}
+		conn := bufio.NewReadWriter(bufio.NewReader(netConn), bufio.NewWriter(netConn))
+		go s.Accept(netConn, conn)
+	}
+
+	var clients []*Client
+	var recvChs []chan []byte
+	errCh := make(chan error, 3)
+	for i := 0; i < numClients; i++ {
+		key := clientPrivateKeys[i]
+		netConn := clientConns[i]
+		conn := bufio.NewReadWriter(bufio.NewReader(netConn), bufio.NewWriter(netConn))
+		c, err := NewClient(key, netConn, conn, t.Logf)
+		if err != nil {
+			t.Fatalf("client %d: %v", i, err)
+		}
+		clients = append(clients, c)
+		recvChs = append(recvChs, make(chan []byte))
+
+		go func(i int) {
+			for {
+				b := make([]byte, 1<<16)
+				n, err := c.Recv(b)
+				if err != nil {
+					errCh <- err
+					return
+				}
+				b = b[:n]
+				recvChs[i] <- b
+			}
+		}(i)
+	}
+
+	recv := func(i int, want string) {
+		t.Helper()
+		select {
+		case b := <-recvChs[i]:
+			if got := string(b); got != want {
+				t.Errorf("client1.Recv=%q, want %q", got, want)
+			}
+		case <-time.After(1 * time.Second):
+			t.Errorf("client%d.Recv, got nothing, want %q", i, want)
+		}
+	}
+	recvNothing := func(i int) {
+		t.Helper()
+		select {
+		case b := <-recvChs[0]:
+			t.Errorf("client%d.Recv=%q, want nothing", i, string(b))
+		default:
+		}
+	}
+
+	msg1 := []byte("hello 0->1\n")
+	if err := clients[0].Send(clientKeys[1], msg1); err != nil {
+		t.Fatal(err)
+	}
+	recv(1, string(msg1))
+	recvNothing(0)
+	recvNothing(2)
+
+	msg2 := []byte("hello 1->2\n")
+	if err := clients[1].Send(clientKeys[2], msg2); err != nil {
+		t.Fatal(err)
+	}
+	recv(2, string(msg2))
+	recvNothing(0)
+	recvNothing(1)
+}