diff options
Diffstat (limited to 'shim/v2/main.go')
-rw-r--r-- | shim/v2/main.go | 298 |
1 files changed, 3 insertions, 295 deletions
diff --git a/shim/v2/main.go b/shim/v2/main.go index 118b6f6e5..41c77394a 100644 --- a/shim/v2/main.go +++ b/shim/v2/main.go @@ -16,303 +16,11 @@ package main import ( - "bytes" - "context" - "flag" - "fmt" - "net" - "os" - "os/exec" - "os/signal" - "path/filepath" - "runtime" - "runtime/debug" - "strings" - "sync" - "syscall" - "time" + "github.com/containerd/containerd/runtime/v2/shim" - "github.com/containerd/containerd/events" - "github.com/containerd/containerd/namespaces" - "github.com/containerd/containerd/runtime/v1/linux/proc" - containerdshim "github.com/containerd/containerd/runtime/v1/shim" - shimapi "github.com/containerd/containerd/runtime/v1/shim/v1" - "github.com/containerd/ttrpc" - "github.com/containerd/typeurl" - ptypes "github.com/gogo/protobuf/types" - "github.com/opencontainers/runc/libcontainer/system" - "github.com/pkg/errors" - "github.com/sirupsen/logrus" - "golang.org/x/sys/unix" - - "gvisor.dev/gvisor/pkg/shim/runsc" - "gvisor.dev/gvisor/pkg/shim/v1/shim" -) - -var ( - debugFlag bool - namespaceFlag string - socketFlag string - addressFlag string - workdirFlag string - runtimeRootFlag string - containerdBinaryFlag string - shimConfigFlag string + runsc "gvisor.dev/gvisor/pkg/shim/v2" ) -// ShimConfigPath is the default shim config file path. -const ShimConfigPath = "/etc/containerd/gvisor-containerd-shim.toml" - -func init() { - flag.BoolVar(&debugFlag, "debug", false, "enable debug output in logs") - flag.StringVar(&namespaceFlag, "namespace", "", "namespace that owns the shim") - flag.StringVar(&socketFlag, "socket", "", "abstract socket path to serve") - flag.StringVar(&addressFlag, "address", "", "grpc address back to main containerd") - flag.StringVar(&workdirFlag, "workdir", "", "path used to storge large temporary data") - // Containerd default to runc, unless another runtime is explicitly specified. - // We keep the same default to make the default behavior consistent. - flag.StringVar(&runtimeRootFlag, "runtime-root", proc.RuncRoot, "root directory for the runtime") - // currently, the `containerd publish` utility is embedded in the daemon binary. - // The daemon invokes `containerd-shim -containerd-binary ...` with its own os.Executable() path. - flag.StringVar(&containerdBinaryFlag, "containerd-binary", "containerd", "path to containerd binary (used for `containerd publish`)") - flag.StringVar(&shimConfigFlag, "config", ShimConfigPath, "path to the shim configuration file") - flag.Parse() -} - func main() { - // This is a hack. Exec current process to run standard containerd-shim - // if runtime root is not `runsc`. We don't need this for shim v2 api. - if filepath.Base(runtimeRootFlag) != "runsc" { - if err := executeRuncShim(); err != nil { - fmt.Fprintf(os.Stderr, "gvisor-containerd-shim: %s\n", err) - os.Exit(1) - } - } - - debug.SetGCPercent(40) - go func() { - for range time.Tick(30 * time.Second) { - debug.FreeOSMemory() - } - }() - - if debugFlag { - logrus.SetLevel(logrus.DebugLevel) - } - - if os.Getenv("GOMAXPROCS") == "" { - // If GOMAXPROCS hasn't been set, we default to a value of 2 to reduce - // the number of Go stacks present in the shim. - runtime.GOMAXPROCS(2) - } - - // Run regular shim if needed. - if err := executeShim(); err != nil { - fmt.Fprintf(os.Stderr, "gvisor-containerd-shim: %s\n", err) - os.Exit(1) - } -} - -// executeRuncShim execs current process to a containerd-shim process and -// retains all flags and envs. -func executeRuncShim() error { - c, err := loadConfig(shimConfigFlag) - if err != nil && !os.IsNotExist(err) { - return errors.Wrap(err, "failed to load shim config") - } - shimPath := c.RuncShim - if shimPath == "" { - shimPath, err = exec.LookPath("containerd-shim") - if err != nil { - return errors.Wrapf(err, "lookup containerd-shim") - } - } - - args := append([]string{shimPath}, os.Args[1:]...) - if err := syscall.Exec(shimPath, args, os.Environ()); err != nil { - return errors.Wrapf(err, "exec containerd-shim %q", shimPath) - } - return nil -} - -func executeShim() error { - // start handling signals as soon as possible so that things are properly reaped - // or if runtime exits before we hit the handler - signals, err := setupSignals() - if err != nil { - return err - } - dump := make(chan os.Signal, 32) - signal.Notify(dump, syscall.SIGUSR1) - - path, err := os.Getwd() - if err != nil { - return err - } - server, err := ttrpc.NewServer(ttrpc.WithServerHandshaker(ttrpc.UnixSocketRequireSameUser())) - if err != nil { - return errors.Wrap(err, "failed creating server") - } - c, err := loadConfig(shimConfigFlag) - if err != nil && !os.IsNotExist(err) { - return errors.Wrap(err, "failed to load shim config") - } - sv, err := shim.NewService( - shim.Config{ - Path: path, - Namespace: namespaceFlag, - WorkDir: workdirFlag, - RuntimeRoot: runtimeRootFlag, - RunscConfig: c.RunscConfig, - }, - &remoteEventsPublisher{address: addressFlag}, - ) - if err != nil { - return err - } - logrus.Debug("registering ttrpc server") - shimapi.RegisterShimService(server, sv) - - socket := socketFlag - if err := serve(server, socket); err != nil { - return err - } - logger := logrus.WithFields(logrus.Fields{ - "pid": os.Getpid(), - "path": path, - "namespace": namespaceFlag, - }) - go func() { - for range dump { - dumpStacks(logger) - } - }() - return handleSignals(logger, signals, server, sv) -} - -// serve serves the ttrpc API over a unix socket at the provided path -// this function does not block -func serve(server *ttrpc.Server, path string) error { - var ( - l net.Listener - err error - ) - if path == "" { - l, err = net.FileListener(os.NewFile(3, "socket")) - path = "[inherited from parent]" - } else { - if len(path) > 106 { - return errors.Errorf("%q: unix socket path too long (> 106)", path) - } - l, err = net.Listen("unix", "\x00"+path) - } - if err != nil { - return err - } - logrus.WithField("socket", path).Debug("serving api on unix socket") - go func() { - defer l.Close() - if err := server.Serve(context.Background(), l); err != nil && - !strings.Contains(err.Error(), "use of closed network connection") { - logrus.WithError(err).Fatal("gvisor-containerd-shim: ttrpc server failure") - } - }() - return nil -} - -// setupSignals creates a new signal handler for all signals and sets the shim as a -// sub-reaper so that the container processes are reparented -func setupSignals() (chan os.Signal, error) { - signals := make(chan os.Signal, 32) - signal.Notify(signals, unix.SIGTERM, unix.SIGINT, unix.SIGCHLD, unix.SIGPIPE) - // make sure runc is setup to use the monitor - // for waiting on processes - // TODO(random-liu): Move shim/reaper.go to a separate package. - runsc.Monitor = containerdshim.Default - // set the shim as the subreaper for all orphaned processes created by the container - if err := system.SetSubreaper(1); err != nil { - return nil, err - } - return signals, nil -} - -func handleSignals(logger *logrus.Entry, signals chan os.Signal, server *ttrpc.Server, sv *shim.Service) error { - var ( - termOnce sync.Once - done = make(chan struct{}) - ) - - for { - select { - case <-done: - return nil - case s := <-signals: - switch s { - case unix.SIGCHLD: - if err := containerdshim.Reap(); err != nil { - logger.WithError(err).Error("reap exit status") - } - case unix.SIGTERM, unix.SIGINT: - go termOnce.Do(func() { - ctx := context.TODO() - if err := server.Shutdown(ctx); err != nil { - logger.WithError(err).Error("failed to shutdown server") - } - // Ensure our child is dead if any - sv.Kill(ctx, &shimapi.KillRequest{ - Signal: uint32(syscall.SIGKILL), - All: true, - }) - sv.Delete(context.Background(), &ptypes.Empty{}) - close(done) - }) - case unix.SIGPIPE: - } - } - } -} - -func dumpStacks(logger *logrus.Entry) { - var ( - buf []byte - stackSize int - ) - bufferLen := 16384 - for stackSize == len(buf) { - buf = make([]byte, bufferLen) - stackSize = runtime.Stack(buf, true) - bufferLen *= 2 - } - buf = buf[:stackSize] - logger.Infof("=== BEGIN goroutine stack dump ===\n%s\n=== END goroutine stack dump ===", buf) -} - -type remoteEventsPublisher struct { - address string -} - -func (l *remoteEventsPublisher) Publish(ctx context.Context, topic string, event events.Event) error { - ns, _ := namespaces.Namespace(ctx) - encoded, err := typeurl.MarshalAny(event) - if err != nil { - return err - } - data, err := encoded.Marshal() - if err != nil { - return err - } - cmd := exec.CommandContext(ctx, containerdBinaryFlag, "--address", l.address, "publish", "--topic", topic, "--namespace", ns) - cmd.Stdin = bytes.NewReader(data) - c, err := containerdshim.Default.Start(cmd) - if err != nil { - return err - } - status, err := containerdshim.Default.Wait(cmd, c) - if err != nil { - return err - } - if status != 0 { - return errors.New("failed to publish event") - } - return nil + shim.Run("io.containerd.runsc.v1", runsc.New) } |