Merge branch 'main' into loopback-wg-proxy

client/internal/daemonaddr/grpc.go

@@ -0,0 +1,42 @@
+package daemonaddr
+
+import (
+	"os"
+	"strconv"
+
+	log "github.com/sirupsen/logrus"
+)
+
+const (
+	// EnvMaxRecvMsgSize overrides the default gRPC max receive message size for
+	// connections to the daemon. Value is in bytes.
+	EnvMaxRecvMsgSize = "NB_DAEMON_GRPC_MAX_MSG_SIZE"
+
+	// defaultMaxRecvMsgSize is the max gRPC receive message size used for daemon
+	// connections when EnvMaxRecvMsgSize is unset or invalid. It overrides the
+	// gRPC library default of 4 MB, which a detailed status already exceeds on a
+	// network of a few thousand peers.
+	defaultMaxRecvMsgSize = 1024 * 1024 * 16
+)
+
+// MaxRecvMsgSize returns the max gRPC receive message size for daemon connections
+// from the environment, or defaultMaxRecvMsgSize (16 MB) if unset or invalid.
+func MaxRecvMsgSize() int {
+	val := os.Getenv(EnvMaxRecvMsgSize)
+	if val == "" {
+		return defaultMaxRecvMsgSize
+	}
+
+	size, err := strconv.Atoi(val)
+	if err != nil {
+		log.Warnf("invalid %s value %q, using default: %v", EnvMaxRecvMsgSize, val, err)
+		return defaultMaxRecvMsgSize
+	}
+
+	if size <= 0 {
+		log.Warnf("invalid %s value %d, must be positive, using default", EnvMaxRecvMsgSize, size)
+		return defaultMaxRecvMsgSize
+	}
+
+	return size
+}

client/internal/daemonaddr/grpc_test.go

@@ -0,0 +1,112 @@
+package daemonaddr
+
+import (
+	"context"
+	"net"
+	"os"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/credentials/insecure"
+	"google.golang.org/grpc/status"
+
+	"github.com/netbirdio/netbird/client/proto"
+)
+
+func TestMaxRecvMsgSize(t *testing.T) {
+	tests := []struct {
+		name     string
+		envValue string
+		expected int
+	}{
+		{name: "unset returns default", envValue: "", expected: defaultMaxRecvMsgSize},
+		{name: "non-numeric returns default", envValue: "abc", expected: defaultMaxRecvMsgSize},
+		{name: "negative returns default", envValue: "-1", expected: defaultMaxRecvMsgSize},
+		{name: "zero returns default", envValue: "0", expected: defaultMaxRecvMsgSize},
+		{name: "valid value is used", envValue: "33554432", expected: 33554432},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			// Set first so the previous value is restored on cleanup, then unset to
+			// exercise the absent case.
+			t.Setenv(EnvMaxRecvMsgSize, tc.envValue)
+			if tc.envValue == "" {
+				require.NoError(t, os.Unsetenv(EnvMaxRecvMsgSize), "unset the override")
+			}
+
+			assert.Equal(t, tc.expected, MaxRecvMsgSize(), "max receive message size")
+		})
+	}
+}
+
+// bigStatusServer answers Status with a response larger than gRPC's 4 MB default
+// receive limit, which is what a detailed status on a large network looks like.
+type bigStatusServer struct {
+	proto.UnimplementedDaemonServiceServer
+	payload string
+}
+
+func (s *bigStatusServer) Status(context.Context, *proto.StatusRequest) (*proto.StatusResponse, error) {
+	return &proto.StatusResponse{Status: s.payload}, nil
+}
+
+func startBigStatusServer(t *testing.T, payload string) string {
+	t.Helper()
+
+	listener, err := net.Listen("tcp", "127.0.0.1:0")
+	require.NoError(t, err, "listen on loopback")
+
+	srv := grpc.NewServer()
+	proto.RegisterDaemonServiceServer(srv, &bigStatusServer{payload: payload})
+	go func() {
+		_ = srv.Serve(listener)
+	}()
+	t.Cleanup(srv.Stop)
+
+	return "tcp://" + listener.Addr().String()
+}
+
+func TestDialTargetAcceptsAStatusOverTheGrpcDefault(t *testing.T) {
+	payload := strings.Repeat("x", 5*1024*1024)
+	addr := startBigStatusServer(t, payload)
+
+	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+	defer cancel()
+
+	target, opts := DialTarget(addr)
+	conn, err := grpc.NewClient(target, opts...)
+	require.NoError(t, err, "dial the daemon")
+	t.Cleanup(func() { _ = conn.Close() })
+
+	resp, err := proto.NewDaemonServiceClient(conn).Status(ctx, &proto.StatusRequest{})
+	require.NoError(t, err, "a detailed status must not be rejected for its size")
+	assert.Len(t, resp.GetStatus(), len(payload), "the whole response must arrive")
+}
+
+// TestDialTargetRaisesTheDefaultLimit is the negative control: the same response
+// over a connection carrying gRPC's own defaults is refused, which is the failure
+// reported by `netbird status -d` on a large deployment.
+func TestDialTargetRaisesTheDefaultLimit(t *testing.T) {
+	payload := strings.Repeat("x", 5*1024*1024)
+	addr := startBigStatusServer(t, payload)
+
+	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+	defer cancel()
+
+	conn, err := grpc.NewClient(
+		strings.TrimPrefix(addr, "tcp://"),
+		grpc.WithTransportCredentials(insecure.NewCredentials()),
+	)
+	require.NoError(t, err, "dial with the library defaults")
+	t.Cleanup(func() { _ = conn.Close() })
+
+	_, err = proto.NewDaemonServiceClient(conn).Status(ctx, &proto.StatusRequest{})
+	require.Error(t, err, "the library default must reject this response")
+	assert.Equal(t, codes.ResourceExhausted, status.Code(err), "gRPC rejects an oversized message")
+}

client/internal/daemonaddr/pipe.go

@@ -36,7 +36,10 @@ const (
 // address. The npipe scheme needs a context dialer because gRPC has no
 // named-pipe resolver; unix and tcp are handled by gRPC itself.
 func DialTarget(addr string) (string, []grpc.DialOption) {
-	opts := []grpc.DialOption{grpc.WithTransportCredentials(insecure.NewCredentials())}
+	opts := []grpc.DialOption{
+		grpc.WithTransportCredentials(insecure.NewCredentials()),
+		grpc.WithDefaultCallOptions(grpc.MaxCallRecvMsgSize(MaxRecvMsgSize())),
+	}
 
 	if name, ok := strings.CutPrefix(addr, pipeScheme); ok {
 		paths := PipePaths(name)

client/internal/elevate/trusted.go

@@ -6,6 +6,17 @@ import (
 	"path/filepath"
 )
 
+// CheckOnlyOwnerWritable reports an error unless path, and every directory
+// leading to it, is owned by an account that can already act with the privileges
+// the caller holds, and is writable by nobody else.
+//
+// Exported for callers outside elevation that read a file while privileged and
+// then act on what it says: the same question this package asks of an
+// executable, asked of a configuration file.
+func CheckOnlyOwnerWritable(path string) error {
+	return checkOnlyOwnerWritable(path)
+}
+
 // trustedSelf returns the path of this executable, provided it is one we are
 // willing to have run as root.
 //

client/internal/engine.go

@@ -1040,7 +1040,11 @@ func (e *Engine) handleSync(update *mgmProto.SyncResponse) error {
 			// back to empty if the FQDN doesn't have the expected shape.
 			dnsName = extractDNSDomainFromFQDN(pc.GetFqdn())
 		}
-		result, err := nbnetworkmap.EnvelopeToNetworkMap(e.ctx, envelope, localKey, dnsName)
+		// With the firewall disabled there is no ACL manager to program, so
+		// RoutesFirewallRules would be built and then dropped. On a peer that
+		// routes many network resources that is the single most expensive
+		// step of the sync.
+		result, err := nbnetworkmap.EnvelopeToNetworkMap(e.ctx, envelope, localKey, dnsName, e.config.DisableFirewall)
 		if err != nil {
 			return fmt.Errorf("decode network map envelope: %w", err)
 		}

client/internal/profilemanager/active_state_test.go

@@ -0,0 +1,76 @@
+package profilemanager
+
+import (
+	"fmt"
+	"sync"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// Regression test: a concurrent Get and Set of the ActiveProfileState will
+// fail on Windows since the write is a temp file renamed over an open file.
+// Windows will refuse to replace a file another handle holds open by default.
+func TestActiveProfileState_ReadsDoNotBreakAConcurrentWrite(t *testing.T) {
+	withTempConfigDir(t, func(configDir string) {
+		withPatchedGlobals(t, configDir, func() {
+			sm := &ServiceManager{}
+			require.NoError(t, sm.CreateDefaultProfile())
+			require.NoError(t, sm.SetActiveProfileStateToDefault())
+
+			const switched = ID("0123456789abcdef0123456789abcdef")
+			const rounds = 50
+
+			var wg sync.WaitGroup
+			errs := make(chan error, 128)
+
+			for i := 0; i < 8; i++ {
+				wg.Add(1)
+				go func() {
+					defer wg.Done()
+					for r := 0; r < rounds; r++ {
+						state, err := sm.GetActiveProfileState()
+						if err != nil {
+							errs <- fmt.Errorf("read: %w", err)
+							return
+						}
+						if state.ID != defaultProfileName && state.ID != switched {
+							errs <- fmt.Errorf("read: active profile is %q, which no writer wrote", state.ID)
+							return
+						}
+					}
+				}()
+			}
+
+			for i := 0; i < 2; i++ {
+				wg.Add(1)
+				go func() {
+					defer wg.Done()
+					for r := 0; r < rounds; r++ {
+						id := switched
+						if r%2 == 0 {
+							id = defaultProfileName
+						}
+						if err := sm.SetActiveProfileState(&ActiveProfileState{ID: id, Username: "testuser"}); err != nil {
+							errs <- fmt.Errorf("switch: %w", err)
+							return
+						}
+					}
+				}()
+			}
+
+			wg.Wait()
+			close(errs)
+
+			for err := range errs {
+				assert.NoError(t, err, "a switch and a read of the active profile state must not collide")
+			}
+
+			state, err := sm.GetActiveProfileState()
+			require.NoError(t, err)
+			assert.Contains(t, []ID{defaultProfileName, switched}, state.ID,
+				"the file holds whichever switch landed last, not a mix of the two")
+		})
+	})
+}

client/internal/wincmd/system32_windows.go

@@ -0,0 +1,30 @@
+// Package wincmd locates the Windows utilities the client shells out to.
+package wincmd
+
+import (
+	"path/filepath"
+
+	log "github.com/sirupsen/logrus"
+	"golang.org/x/sys/windows"
+)
+
+// defaultSystem32Dir is where the system directory is on every supported
+// install, used only when the API that reports it fails.
+const defaultSystem32Dir = `C:\Windows\System32`
+
+// System32 returns the full path of a Windows utility under the system
+// directory.
+//
+// PATH is deliberately not consulted. The daemon runs as LocalSystem with an
+// environment of its own, so whoever can place an entry in that PATH chooses
+// which binary runs with those privileges. The system directory is read from
+// the API rather than from %SystemRoot% for the same reason.
+func System32(command string) string {
+	sysDir, err := windows.GetSystemDirectory()
+	if err != nil {
+		log.Warnf("Failed to locate the Windows system directory, falling back to %s: %v", defaultSystem32Dir, err)
+		sysDir = defaultSystem32Dir
+	}
+
+	return filepath.Join(sysDir, command+".exe")
+}

client/internal/wincmd/system32_windows_test.go

@@ -0,0 +1,31 @@
+package wincmd
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestSystem32IgnoresPATH(t *testing.T) {
+	// A directory holding something that would win a PATH lookup, in front of
+	// everything else: the daemon runs as LocalSystem, so a PATH entry must not
+	// be able to decide what it executes.
+	planted := t.TempDir()
+	require.NoError(t, os.WriteFile(filepath.Join(planted, "netsh.exe"), []byte("not really netsh"), 0o600))
+	t.Setenv("PATH", planted+string(os.PathListSeparator)+os.Getenv("PATH"))
+
+	got := System32("netsh")
+
+	assert.True(t, filepath.IsAbs(got), "the path must be absolute, got %q", got)
+	assert.NotContains(t, got, planted, "a PATH entry must not be consulted")
+	assert.True(t, strings.EqualFold(filepath.Base(got), "netsh.exe"), "unexpected file name in %q", got)
+
+	// The system directory is what Windows reports it to be, not %SystemRoot%,
+	// which the same caller could have set alongside PATH.
+	t.Setenv("SystemRoot", planted)
+	assert.Equal(t, got, System32("netsh"), "%SystemRoot% must not move the lookup")
+}