Merge pull request #1767 from stevvooe/ttrpc-shim

linux/shim: reduce memory overhead by using ttrpc

Protobuild.toml

@@ -32,9 +32,13 @@ plugins = ["grpc", "fieldpath"]
   "google/rpc/status.proto" = "github.com/containerd/containerd/protobuf/google/rpc"
 
 [[overrides]]
-
 prefixes = ["github.com/containerd/containerd/api/events"]
-plugins = ["fieldpath"]
+plugins = ["fieldpath"] # disable grpc for this package
+
+[[overrides]]
+# enable ttrpc and disable fieldpath and grpc for the shim
+prefixes = ["github.com/containerd/containerd/linux/shim/v1"]
+plugins = ["ttrpc"]
 
 # Aggregrate the API descriptors to lock down API changes.
 [[descriptors]]

cmd/containerd-shim/main_unix.go

@@ -25,8 +25,8 @@ import (
 	"github.com/containerd/typeurl"
 	ptypes "github.com/gogo/protobuf/types"
 	"github.com/sirupsen/logrus"
+	"github.com/stevvooe/ttrpc"
 	"golang.org/x/sys/unix"
-	"google.golang.org/grpc"
 )
 
 var (
@@ -100,7 +100,8 @@ func executeShim() error {
 		return err
 	}
 	logrus.Debug("registering grpc server")
-	shimapi.RegisterShimServer(server, sv)
+	shimapi.RegisterShimService(server, sv)
+
 	socket := socketFlag
 	if err := serve(server, socket); err != nil {
 		return err
@@ -115,7 +116,7 @@ func executeShim() error {
 
 // serve serves the grpc API over a unix socket at the provided path
 // this function does not block
-func serve(server *grpc.Server, path string) error {
+func serve(server *ttrpc.Server, path string) error {
 	var (
 		l   net.Listener
 		err error
@@ -140,7 +141,7 @@ func serve(server *grpc.Server, path string) error {
 	return nil
 }
 
-func handleSignals(logger *logrus.Entry, signals chan os.Signal, server *grpc.Server, sv *shim.Service) error {
+func handleSignals(logger *logrus.Entry, signals chan os.Signal, server *ttrpc.Server, sv *shim.Service) error {
 	var (
 		termOnce sync.Once
 		done     = make(chan struct{})
@@ -158,9 +159,12 @@ func handleSignals(logger *logrus.Entry, signals chan os.Signal, server *grpc.Se
 				}
 			case unix.SIGTERM, unix.SIGINT:
 				go termOnce.Do(func() {
-					server.Stop()
+					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(context.Background(), &shimapi.KillRequest{
+					sv.Kill(ctx, &shimapi.KillRequest{
 						Signal: uint32(syscall.SIGKILL),
 						All:    true,
 					})

cmd/containerd-shim/shim_linux.go

@@ -1,20 +1,13 @@
 package main
 
 import (
-	"net"
 	"os"
 	"os/signal"
 
-	"google.golang.org/grpc"
-	"google.golang.org/grpc/credentials"
-
-	"golang.org/x/net/context"
-	"golang.org/x/sys/unix"
-
 	"github.com/containerd/containerd/reaper"
 	"github.com/containerd/containerd/sys"
 	runc "github.com/containerd/go-runc"
-	"github.com/pkg/errors"
+	"github.com/stevvooe/ttrpc"
 )
 
 // setupSignals creates a new signal handler for all signals and sets the shim as a
@@ -32,64 +25,6 @@ func setupSignals() (chan os.Signal, error) {
 	return signals, nil
 }
 
-func newServer() *grpc.Server {
+func newServer() *ttrpc.Server {
-	return grpc.NewServer(grpc.Creds(NewUnixSocketCredentials(0, 0)))
+	return ttrpc.NewServer()
-}
-
-type unixSocketCredentials struct {
-	uid        int
-	gid        int
-	serverName string
-}
-
-// NewUnixSocketCredentials returns TransportCredentials for a local unix socket
-func NewUnixSocketCredentials(uid, gid int) credentials.TransportCredentials {
-	return &unixSocketCredentials{uid, gid, "locahost"}
-}
-
-func (u *unixSocketCredentials) ClientHandshake(ctx context.Context, addr string, rawConn net.Conn) (net.Conn, credentials.AuthInfo, error) {
-	return nil, nil, errors.New("ClientHandshake is not supported by unixSocketCredentials")
-}
-
-func (u *unixSocketCredentials) ServerHandshake(c net.Conn) (net.Conn, credentials.AuthInfo, error) {
-	uc, ok := c.(*net.UnixConn)
-	if !ok {
-		return nil, nil, errors.New("unixSocketCredentials only supports unix socket")
-	}
-
-	f, err := uc.File()
-	if err != nil {
-		return nil, nil, errors.Wrap(err, "unixSocketCredentials: failed to retrieve connection underlying fd")
-	}
-	pcred, err := unix.GetsockoptUcred(int(f.Fd()), unix.SOL_SOCKET, unix.SO_PEERCRED)
-	if err != nil {
-		return nil, nil, errors.Wrap(err, "unixSocketCredentials: failed to retrieve socket peer credentials")
-	}
-
-	if (u.uid != -1 && uint32(u.uid) != pcred.Uid) || (u.gid != -1 && uint32(u.gid) != pcred.Gid) {
-		return nil, nil, errors.New("unixSocketCredentials: invalid credentials")
-	}
-
-	return c, u, nil
-}
-
-func (u *unixSocketCredentials) Info() credentials.ProtocolInfo {
-	return credentials.ProtocolInfo{
-		SecurityProtocol: "unix-socket-peer-creds",
-		SecurityVersion:  "1.0",
-		ServerName:       u.serverName,
-	}
-}
-
-func (u *unixSocketCredentials) Clone() credentials.TransportCredentials {
-	return &unixSocketCredentials{u.uid, u.gid, u.serverName}
-}
-
-func (u *unixSocketCredentials) OverrideServerName(serverName string) error {
-	u.serverName = serverName
-	return nil
-}
-
-func (u *unixSocketCredentials) AuthType() string {
-	return "unix-socket-peer-creds"
 }

cmd/containerd-shim/shim_unix.go

@@ -6,10 +6,9 @@ import (
 	"os"
 	"os/signal"
 
-	"google.golang.org/grpc"
-
 	"github.com/containerd/containerd/reaper"
 	runc "github.com/containerd/go-runc"
+	"github.com/stevvooe/ttrpc"
 )
 
 // setupSignals creates a new signal handler for all signals and sets the shim as a
@@ -23,6 +22,6 @@ func setupSignals() (chan os.Signal, error) {
 	return signals, nil
 }
 
-func newServer() *grpc.Server {
+func newServer() *ttrpc.Server {
-	return grpc.NewServer()
+	return ttrpc.NewServer()
 }

cmd/ctr/commands/shim/shim.go

@@ -6,12 +6,9 @@ import (
 	"fmt"
 	"io/ioutil"
 	"net"
-	"time"
 
 	gocontext "context"
 
-	"google.golang.org/grpc"
-
 	"github.com/containerd/console"
 	"github.com/containerd/containerd/cmd/ctr/commands"
 	shim "github.com/containerd/containerd/linux/shim/v1"
@@ -20,6 +17,7 @@ import (
 	"github.com/opencontainers/runtime-spec/specs-go"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
+	"github.com/stevvooe/ttrpc"
 	"github.com/urfave/cli"
 )
 
@@ -212,21 +210,21 @@ var execCommand = cli.Command{
 	},
 }
 
-func getShimService(context *cli.Context) (shim.ShimClient, error) {
+func getShimService(context *cli.Context) (shim.ShimService, error) {
 	bindSocket := context.GlobalString("socket")
 	if bindSocket == "" {
 		return nil, errors.New("socket path must be specified")
 	}
 
-	dialOpts := []grpc.DialOption{grpc.WithInsecure(), grpc.WithTimeout(100 * time.Second)}
+	conn, err := net.Dial("unix", "\x00"+bindSocket)
-	dialOpts = append(dialOpts,
-		grpc.WithDialer(func(addr string, timeout time.Duration) (net.Conn, error) {
-			return net.DialTimeout("unix", "\x00"+bindSocket, timeout)
-		},
-		))
-	conn, err := grpc.Dial(fmt.Sprintf("unix://%s", bindSocket), dialOpts...)
 	if err != nil {
 		return nil, err
 	}
-	return shim.NewShimClient(conn), nil
+
+	client := ttrpc.NewClient(conn)
+
+	// TODO(stevvooe): This actually leaks the connection. We were leaking it
+	// before, so may not be a huge deal.
+
+	return shim.NewShimClient(client), nil
 }

cmd/protoc-gen-gogoctrd/main.go

@@ -5,6 +5,7 @@ import (
 	"github.com/gogo/protobuf/protoc-gen-gogo/descriptor"
 	"github.com/gogo/protobuf/vanity"
 	"github.com/gogo/protobuf/vanity/command"
+	_ "github.com/stevvooe/ttrpc/plugin"
 )
 
 func main() {

linux/shim/client/client.go

@@ -4,7 +4,6 @@ package client
 
 import (
 	"context"
-	"fmt"
 	"io"
 	"net"
 	"os"
@@ -18,6 +17,7 @@ import (
 
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
+	"github.com/stevvooe/ttrpc"
 
 	"github.com/containerd/containerd/events"
 	"github.com/containerd/containerd/linux/shim"
@@ -26,17 +26,16 @@ import (
 	"github.com/containerd/containerd/reaper"
 	"github.com/containerd/containerd/sys"
 	ptypes "github.com/gogo/protobuf/types"
-	"google.golang.org/grpc"
 )
 
 var empty = &ptypes.Empty{}
 
 // Opt is an option for a shim client configuration
-type Opt func(context.Context, shim.Config) (shimapi.ShimClient, io.Closer, error)
+type Opt func(context.Context, shim.Config) (shimapi.ShimService, io.Closer, error)
 
 // WithStart executes a new shim process
 func WithStart(binary, address, daemonAddress, cgroup string, nonewns, debug bool, exitHandler func()) Opt {
-	return func(ctx context.Context, config shim.Config) (_ shimapi.ShimClient, _ io.Closer, err error) {
+	return func(ctx context.Context, config shim.Config) (_ shimapi.ShimService, _ io.Closer, err error) {
 		socket, err := newSocket(address)
 		if err != nil {
 			return nil, nil, err
@@ -139,19 +138,8 @@ func newSocket(address string) (*net.UnixListener, error) {
 	return l.(*net.UnixListener), nil
 }
 
-func connect(address string, d func(string, time.Duration) (net.Conn, error)) (*grpc.ClientConn, error) {
+func connect(address string, d func(string, time.Duration) (net.Conn, error)) (net.Conn, error) {
-	gopts := []grpc.DialOption{
+	return d(address, 100*time.Second)
-		grpc.WithBlock(),
-		grpc.WithInsecure(),
-		grpc.WithTimeout(100 * time.Second),
-		grpc.WithDialer(d),
-		grpc.FailOnNonTempDialError(true),
-	}
-	conn, err := grpc.Dial(dialAddress(address), gopts...)
-	if err != nil {
-		return nil, errors.Wrapf(err, "failed to dial %q", address)
-	}
-	return conn, nil
 }
 
 func annonDialer(address string, timeout time.Duration) (net.Conn, error) {
@@ -159,24 +147,20 @@ func annonDialer(address string, timeout time.Duration) (net.Conn, error) {
 	return net.DialTimeout("unix", "\x00"+address, timeout)
 }
 
-func dialAddress(address string) string {
-	return fmt.Sprintf("unix://%s", address)
-}
-
 // WithConnect connects to an existing shim
 func WithConnect(address string) Opt {
-	return func(ctx context.Context, config shim.Config) (shimapi.ShimClient, io.Closer, error) {
+	return func(ctx context.Context, config shim.Config) (shimapi.ShimService, io.Closer, error) {
 		conn, err := connect(address, annonDialer)
 		if err != nil {
 			return nil, nil, err
 		}
-		return shimapi.NewShimClient(conn), conn, nil
+		return shimapi.NewShimClient(ttrpc.NewClient(conn)), conn, nil
 	}
 }
 
 // WithLocal uses an in process shim
-func WithLocal(publisher events.Publisher) func(context.Context, shim.Config) (shimapi.ShimClient, io.Closer, error) {
+func WithLocal(publisher events.Publisher) func(context.Context, shim.Config) (shimapi.ShimService, io.Closer, error) {
-	return func(ctx context.Context, config shim.Config) (shimapi.ShimClient, io.Closer, error) {
+	return func(ctx context.Context, config shim.Config) (shimapi.ShimService, io.Closer, error) {
 		service, err := shim.NewService(config, publisher)
 		if err != nil {
 			return nil, nil, err
@@ -192,7 +176,7 @@ func New(ctx context.Context, config shim.Config, opt Opt) (*Client, error) {
 		return nil, err
 	}
 	return &Client{
-		ShimClient: s,
+		ShimService: s,
 		c:           c,
 		exitCh:      make(chan struct{}),
 	}, nil
@@ -200,7 +184,7 @@ func New(ctx context.Context, config shim.Config, opt Opt) (*Client, error) {
 
 // Client is a shim client containing the connection to a shim
 type Client struct {
-	shimapi.ShimClient
+	shimapi.ShimService
 
 	c        io.Closer
 	exitCh   chan struct{}
@@ -212,11 +196,10 @@ type Client struct {
 func (c *Client) IsAlive(ctx context.Context) (bool, error) {
 	_, err := c.ShimInfo(ctx, empty)
 	if err != nil {
-		if err != grpc.ErrServerStopped {
+		// TODO(stevvooe): There are some error conditions that need to be
+		// handle with unix sockets existence to give the right answer here.
 		return false, err
 	}
-		return false, nil
-	}
 	return true, nil
 }
 

linux/shim/local.go

@@ -3,17 +3,16 @@
 package shim
 
 import (
+	"context"
 	"path/filepath"
 
 	shimapi "github.com/containerd/containerd/linux/shim/v1"
 	ptypes "github.com/gogo/protobuf/types"
-	"golang.org/x/net/context"
 	"golang.org/x/sys/unix"
-	"google.golang.org/grpc"
 )
 
 // NewLocal returns a shim client implementation for issue commands to a shim
-func NewLocal(s *Service) shimapi.ShimClient {
+func NewLocal(s *Service) shimapi.ShimService {
 	return &local{
 		s: s,
 	}
@@ -23,15 +22,15 @@ type local struct {
 	s *Service
 }
 
-func (c *local) Create(ctx context.Context, in *shimapi.CreateTaskRequest, opts ...grpc.CallOption) (*shimapi.CreateTaskResponse, error) {
+func (c *local) Create(ctx context.Context, in *shimapi.CreateTaskRequest) (*shimapi.CreateTaskResponse, error) {
 	return c.s.Create(ctx, in)
 }
 
-func (c *local) Start(ctx context.Context, in *shimapi.StartRequest, opts ...grpc.CallOption) (*shimapi.StartResponse, error) {
+func (c *local) Start(ctx context.Context, in *shimapi.StartRequest) (*shimapi.StartResponse, error) {
 	return c.s.Start(ctx, in)
 }
 
-func (c *local) Delete(ctx context.Context, in *ptypes.Empty, opts ...grpc.CallOption) (*shimapi.DeleteResponse, error) {
+func (c *local) Delete(ctx context.Context, in *ptypes.Empty) (*shimapi.DeleteResponse, error) {
 	// make sure we unmount the containers rootfs for this local
 	if err := unix.Unmount(filepath.Join(c.s.config.Path, "rootfs"), 0); err != nil {
 		return nil, err
@@ -39,54 +38,54 @@ func (c *local) Delete(ctx context.Context, in *ptypes.Empty, opts ...grpc.CallO
 	return c.s.Delete(ctx, in)
 }
 
-func (c *local) DeleteProcess(ctx context.Context, in *shimapi.DeleteProcessRequest, opts ...grpc.CallOption) (*shimapi.DeleteResponse, error) {
+func (c *local) DeleteProcess(ctx context.Context, in *shimapi.DeleteProcessRequest) (*shimapi.DeleteResponse, error) {
 	return c.s.DeleteProcess(ctx, in)
 }
 
-func (c *local) Exec(ctx context.Context, in *shimapi.ExecProcessRequest, opts ...grpc.CallOption) (*ptypes.Empty, error) {
+func (c *local) Exec(ctx context.Context, in *shimapi.ExecProcessRequest) (*ptypes.Empty, error) {
 	return c.s.Exec(ctx, in)
 }
 
-func (c *local) ResizePty(ctx context.Context, in *shimapi.ResizePtyRequest, opts ...grpc.CallOption) (*ptypes.Empty, error) {
+func (c *local) ResizePty(ctx context.Context, in *shimapi.ResizePtyRequest) (*ptypes.Empty, error) {
 	return c.s.ResizePty(ctx, in)
 }
 
-func (c *local) State(ctx context.Context, in *shimapi.StateRequest, opts ...grpc.CallOption) (*shimapi.StateResponse, error) {
+func (c *local) State(ctx context.Context, in *shimapi.StateRequest) (*shimapi.StateResponse, error) {
 	return c.s.State(ctx, in)
 }
 
-func (c *local) Pause(ctx context.Context, in *ptypes.Empty, opts ...grpc.CallOption) (*ptypes.Empty, error) {
+func (c *local) Pause(ctx context.Context, in *ptypes.Empty) (*ptypes.Empty, error) {
 	return c.s.Pause(ctx, in)
 }
 
-func (c *local) Resume(ctx context.Context, in *ptypes.Empty, opts ...grpc.CallOption) (*ptypes.Empty, error) {
+func (c *local) Resume(ctx context.Context, in *ptypes.Empty) (*ptypes.Empty, error) {
 	return c.s.Resume(ctx, in)
 }
 
-func (c *local) Kill(ctx context.Context, in *shimapi.KillRequest, opts ...grpc.CallOption) (*ptypes.Empty, error) {
+func (c *local) Kill(ctx context.Context, in *shimapi.KillRequest) (*ptypes.Empty, error) {
 	return c.s.Kill(ctx, in)
 }
 
-func (c *local) ListPids(ctx context.Context, in *shimapi.ListPidsRequest, opts ...grpc.CallOption) (*shimapi.ListPidsResponse, error) {
+func (c *local) ListPids(ctx context.Context, in *shimapi.ListPidsRequest) (*shimapi.ListPidsResponse, error) {
 	return c.s.ListPids(ctx, in)
 }
 
-func (c *local) CloseIO(ctx context.Context, in *shimapi.CloseIORequest, opts ...grpc.CallOption) (*ptypes.Empty, error) {
+func (c *local) CloseIO(ctx context.Context, in *shimapi.CloseIORequest) (*ptypes.Empty, error) {
 	return c.s.CloseIO(ctx, in)
 }
 
-func (c *local) Checkpoint(ctx context.Context, in *shimapi.CheckpointTaskRequest, opts ...grpc.CallOption) (*ptypes.Empty, error) {
+func (c *local) Checkpoint(ctx context.Context, in *shimapi.CheckpointTaskRequest) (*ptypes.Empty, error) {
 	return c.s.Checkpoint(ctx, in)
 }
 
-func (c *local) ShimInfo(ctx context.Context, in *ptypes.Empty, opts ...grpc.CallOption) (*shimapi.ShimInfoResponse, error) {
+func (c *local) ShimInfo(ctx context.Context, in *ptypes.Empty) (*shimapi.ShimInfoResponse, error) {
 	return c.s.ShimInfo(ctx, in)
 }
 
-func (c *local) Update(ctx context.Context, in *shimapi.UpdateTaskRequest, opts ...grpc.CallOption) (*ptypes.Empty, error) {
+func (c *local) Update(ctx context.Context, in *shimapi.UpdateTaskRequest) (*ptypes.Empty, error) {
 	return c.s.Update(ctx, in)
 }
 
-func (c *local) Wait(ctx context.Context, in *shimapi.WaitRequest, opts ...grpc.CallOption) (*shimapi.WaitResponse, error) {
+func (c *local) Wait(ctx context.Context, in *shimapi.WaitRequest) (*shimapi.WaitResponse, error) {
 	return c.s.Wait(ctx, in)
 }

linux/shim/service.go

@@ -3,13 +3,11 @@
 package shim
 
 import (
+	"context"
 	"fmt"
 	"os"
 	"sync"
 
-	"google.golang.org/grpc"
-	"google.golang.org/grpc/codes"
-
 	"github.com/containerd/console"
 	eventstypes "github.com/containerd/containerd/api/events"
 	"github.com/containerd/containerd/api/types/task"
@@ -27,7 +25,8 @@ import (
 	ptypes "github.com/gogo/protobuf/types"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
-	"golang.org/x/net/context"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
 )
 
 var empty = &ptypes.Empty{}
@@ -167,7 +166,7 @@ func (s *Service) DeleteProcess(ctx context.Context, r *shimapi.DeleteProcessReq
 	s.mu.Lock()
 	defer s.mu.Unlock()
 	if r.ID == s.id {
-		return nil, grpc.Errorf(codes.InvalidArgument, "cannot delete init process with DeleteProcess")
+		return nil, status.Errorf(codes.InvalidArgument, "cannot delete init process with DeleteProcess")
 	}
 	p := s.processes[r.ID]
 	if p == nil {

linux/shim/v1/shim.pb.go

@@ -44,16 +44,14 @@ import containerd_v1_types "github.com/containerd/containerd/api/types/task"
 
 import time "time"
 
-import (
-	context "golang.org/x/net/context"
-	grpc "google.golang.org/grpc"
-)
-
 import github_com_gogo_protobuf_types "github.com/gogo/protobuf/types"
 
 import strings "strings"
 import reflect "reflect"
 
+import context "context"
+import github_com_stevvooe_ttrpc "github.com/stevvooe/ttrpc"
+
 import io "io"
 
 // Reference imports to suppress errors if they are not otherwise used.
@@ -283,578 +281,6 @@ func init() {
 	proto.RegisterType((*WaitRequest)(nil), "containerd.runtime.linux.shim.v1.WaitRequest")
 	proto.RegisterType((*WaitResponse)(nil), "containerd.runtime.linux.shim.v1.WaitResponse")
 }
-
-// Reference imports to suppress errors if they are not otherwise used.
-var _ context.Context
-var _ grpc.ClientConn
-
-// This is a compile-time assertion to ensure that this generated file
-// is compatible with the grpc package it is being compiled against.
-const _ = grpc.SupportPackageIsVersion4
-
-// Client API for Shim service
-
-type ShimClient interface {
-	// State returns shim and task state information.
-	State(ctx context.Context, in *StateRequest, opts ...grpc.CallOption) (*StateResponse, error)
-	Create(ctx context.Context, in *CreateTaskRequest, opts ...grpc.CallOption) (*CreateTaskResponse, error)
-	Start(ctx context.Context, in *StartRequest, opts ...grpc.CallOption) (*StartResponse, error)
-	Delete(ctx context.Context, in *google_protobuf1.Empty, opts ...grpc.CallOption) (*DeleteResponse, error)
-	DeleteProcess(ctx context.Context, in *DeleteProcessRequest, opts ...grpc.CallOption) (*DeleteResponse, error)
-	ListPids(ctx context.Context, in *ListPidsRequest, opts ...grpc.CallOption) (*ListPidsResponse, error)
-	Pause(ctx context.Context, in *google_protobuf1.Empty, opts ...grpc.CallOption) (*google_protobuf1.Empty, error)
-	Resume(ctx context.Context, in *google_protobuf1.Empty, opts ...grpc.CallOption) (*google_protobuf1.Empty, error)
-	Checkpoint(ctx context.Context, in *CheckpointTaskRequest, opts ...grpc.CallOption) (*google_protobuf1.Empty, error)
-	Kill(ctx context.Context, in *KillRequest, opts ...grpc.CallOption) (*google_protobuf1.Empty, error)
-	Exec(ctx context.Context, in *ExecProcessRequest, opts ...grpc.CallOption) (*google_protobuf1.Empty, error)
-	ResizePty(ctx context.Context, in *ResizePtyRequest, opts ...grpc.CallOption) (*google_protobuf1.Empty, error)
-	CloseIO(ctx context.Context, in *CloseIORequest, opts ...grpc.CallOption) (*google_protobuf1.Empty, error)
-	// ShimInfo returns information about the shim.
-	ShimInfo(ctx context.Context, in *google_protobuf1.Empty, opts ...grpc.CallOption) (*ShimInfoResponse, error)
-	Update(ctx context.Context, in *UpdateTaskRequest, opts ...grpc.CallOption) (*google_protobuf1.Empty, error)
-	Wait(ctx context.Context, in *WaitRequest, opts ...grpc.CallOption) (*WaitResponse, error)
-}
-
-type shimClient struct {
-	cc *grpc.ClientConn
-}
-
-func NewShimClient(cc *grpc.ClientConn) ShimClient {
-	return &shimClient{cc}
-}
-
-func (c *shimClient) State(ctx context.Context, in *StateRequest, opts ...grpc.CallOption) (*StateResponse, error) {
-	out := new(StateResponse)
-	err := grpc.Invoke(ctx, "/containerd.runtime.linux.shim.v1.Shim/State", in, out, c.cc, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *shimClient) Create(ctx context.Context, in *CreateTaskRequest, opts ...grpc.CallOption) (*CreateTaskResponse, error) {
-	out := new(CreateTaskResponse)
-	err := grpc.Invoke(ctx, "/containerd.runtime.linux.shim.v1.Shim/Create", in, out, c.cc, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *shimClient) Start(ctx context.Context, in *StartRequest, opts ...grpc.CallOption) (*StartResponse, error) {
-	out := new(StartResponse)
-	err := grpc.Invoke(ctx, "/containerd.runtime.linux.shim.v1.Shim/Start", in, out, c.cc, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *shimClient) Delete(ctx context.Context, in *google_protobuf1.Empty, opts ...grpc.CallOption) (*DeleteResponse, error) {
-	out := new(DeleteResponse)
-	err := grpc.Invoke(ctx, "/containerd.runtime.linux.shim.v1.Shim/Delete", in, out, c.cc, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *shimClient) DeleteProcess(ctx context.Context, in *DeleteProcessRequest, opts ...grpc.CallOption) (*DeleteResponse, error) {
-	out := new(DeleteResponse)
-	err := grpc.Invoke(ctx, "/containerd.runtime.linux.shim.v1.Shim/DeleteProcess", in, out, c.cc, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *shimClient) ListPids(ctx context.Context, in *ListPidsRequest, opts ...grpc.CallOption) (*ListPidsResponse, error) {
-	out := new(ListPidsResponse)
-	err := grpc.Invoke(ctx, "/containerd.runtime.linux.shim.v1.Shim/ListPids", in, out, c.cc, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *shimClient) Pause(ctx context.Context, in *google_protobuf1.Empty, opts ...grpc.CallOption) (*google_protobuf1.Empty, error) {
-	out := new(google_protobuf1.Empty)
-	err := grpc.Invoke(ctx, "/containerd.runtime.linux.shim.v1.Shim/Pause", in, out, c.cc, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *shimClient) Resume(ctx context.Context, in *google_protobuf1.Empty, opts ...grpc.CallOption) (*google_protobuf1.Empty, error) {
-	out := new(google_protobuf1.Empty)
-	err := grpc.Invoke(ctx, "/containerd.runtime.linux.shim.v1.Shim/Resume", in, out, c.cc, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *shimClient) Checkpoint(ctx context.Context, in *CheckpointTaskRequest, opts ...grpc.CallOption) (*google_protobuf1.Empty, error) {
-	out := new(google_protobuf1.Empty)
-	err := grpc.Invoke(ctx, "/containerd.runtime.linux.shim.v1.Shim/Checkpoint", in, out, c.cc, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *shimClient) Kill(ctx context.Context, in *KillRequest, opts ...grpc.CallOption) (*google_protobuf1.Empty, error) {
-	out := new(google_protobuf1.Empty)
-	err := grpc.Invoke(ctx, "/containerd.runtime.linux.shim.v1.Shim/Kill", in, out, c.cc, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *shimClient) Exec(ctx context.Context, in *ExecProcessRequest, opts ...grpc.CallOption) (*google_protobuf1.Empty, error) {
-	out := new(google_protobuf1.Empty)
-	err := grpc.Invoke(ctx, "/containerd.runtime.linux.shim.v1.Shim/Exec", in, out, c.cc, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *shimClient) ResizePty(ctx context.Context, in *ResizePtyRequest, opts ...grpc.CallOption) (*google_protobuf1.Empty, error) {
-	out := new(google_protobuf1.Empty)
-	err := grpc.Invoke(ctx, "/containerd.runtime.linux.shim.v1.Shim/ResizePty", in, out, c.cc, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *shimClient) CloseIO(ctx context.Context, in *CloseIORequest, opts ...grpc.CallOption) (*google_protobuf1.Empty, error) {
-	out := new(google_protobuf1.Empty)
-	err := grpc.Invoke(ctx, "/containerd.runtime.linux.shim.v1.Shim/CloseIO", in, out, c.cc, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *shimClient) ShimInfo(ctx context.Context, in *google_protobuf1.Empty, opts ...grpc.CallOption) (*ShimInfoResponse, error) {
-	out := new(ShimInfoResponse)
-	err := grpc.Invoke(ctx, "/containerd.runtime.linux.shim.v1.Shim/ShimInfo", in, out, c.cc, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *shimClient) Update(ctx context.Context, in *UpdateTaskRequest, opts ...grpc.CallOption) (*google_protobuf1.Empty, error) {
-	out := new(google_protobuf1.Empty)
-	err := grpc.Invoke(ctx, "/containerd.runtime.linux.shim.v1.Shim/Update", in, out, c.cc, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *shimClient) Wait(ctx context.Context, in *WaitRequest, opts ...grpc.CallOption) (*WaitResponse, error) {
-	out := new(WaitResponse)
-	err := grpc.Invoke(ctx, "/containerd.runtime.linux.shim.v1.Shim/Wait", in, out, c.cc, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-// Server API for Shim service
-
-type ShimServer interface {
-	// State returns shim and task state information.
-	State(context.Context, *StateRequest) (*StateResponse, error)
-	Create(context.Context, *CreateTaskRequest) (*CreateTaskResponse, error)
-	Start(context.Context, *StartRequest) (*StartResponse, error)
-	Delete(context.Context, *google_protobuf1.Empty) (*DeleteResponse, error)
-	DeleteProcess(context.Context, *DeleteProcessRequest) (*DeleteResponse, error)
-	ListPids(context.Context, *ListPidsRequest) (*ListPidsResponse, error)
-	Pause(context.Context, *google_protobuf1.Empty) (*google_protobuf1.Empty, error)
-	Resume(context.Context, *google_protobuf1.Empty) (*google_protobuf1.Empty, error)
-	Checkpoint(context.Context, *CheckpointTaskRequest) (*google_protobuf1.Empty, error)
-	Kill(context.Context, *KillRequest) (*google_protobuf1.Empty, error)
-	Exec(context.Context, *ExecProcessRequest) (*google_protobuf1.Empty, error)
-	ResizePty(context.Context, *ResizePtyRequest) (*google_protobuf1.Empty, error)
-	CloseIO(context.Context, *CloseIORequest) (*google_protobuf1.Empty, error)
-	// ShimInfo returns information about the shim.
-	ShimInfo(context.Context, *google_protobuf1.Empty) (*ShimInfoResponse, error)
-	Update(context.Context, *UpdateTaskRequest) (*google_protobuf1.Empty, error)
-	Wait(context.Context, *WaitRequest) (*WaitResponse, error)
-}
-
-func RegisterShimServer(s *grpc.Server, srv ShimServer) {
-	s.RegisterService(&_Shim_serviceDesc, srv)
-}
-
-func _Shim_State_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(StateRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(ShimServer).State(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: "/containerd.runtime.linux.shim.v1.Shim/State",
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(ShimServer).State(ctx, req.(*StateRequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _Shim_Create_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(CreateTaskRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(ShimServer).Create(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: "/containerd.runtime.linux.shim.v1.Shim/Create",
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(ShimServer).Create(ctx, req.(*CreateTaskRequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _Shim_Start_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(StartRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(ShimServer).Start(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: "/containerd.runtime.linux.shim.v1.Shim/Start",
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(ShimServer).Start(ctx, req.(*StartRequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _Shim_Delete_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(google_protobuf1.Empty)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(ShimServer).Delete(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: "/containerd.runtime.linux.shim.v1.Shim/Delete",
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(ShimServer).Delete(ctx, req.(*google_protobuf1.Empty))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _Shim_DeleteProcess_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(DeleteProcessRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(ShimServer).DeleteProcess(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: "/containerd.runtime.linux.shim.v1.Shim/DeleteProcess",
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(ShimServer).DeleteProcess(ctx, req.(*DeleteProcessRequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _Shim_ListPids_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(ListPidsRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(ShimServer).ListPids(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: "/containerd.runtime.linux.shim.v1.Shim/ListPids",
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(ShimServer).ListPids(ctx, req.(*ListPidsRequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _Shim_Pause_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(google_protobuf1.Empty)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(ShimServer).Pause(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: "/containerd.runtime.linux.shim.v1.Shim/Pause",
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(ShimServer).Pause(ctx, req.(*google_protobuf1.Empty))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _Shim_Resume_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(google_protobuf1.Empty)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(ShimServer).Resume(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: "/containerd.runtime.linux.shim.v1.Shim/Resume",
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(ShimServer).Resume(ctx, req.(*google_protobuf1.Empty))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _Shim_Checkpoint_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(CheckpointTaskRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(ShimServer).Checkpoint(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: "/containerd.runtime.linux.shim.v1.Shim/Checkpoint",
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(ShimServer).Checkpoint(ctx, req.(*CheckpointTaskRequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _Shim_Kill_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(KillRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(ShimServer).Kill(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: "/containerd.runtime.linux.shim.v1.Shim/Kill",
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(ShimServer).Kill(ctx, req.(*KillRequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _Shim_Exec_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(ExecProcessRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(ShimServer).Exec(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: "/containerd.runtime.linux.shim.v1.Shim/Exec",
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(ShimServer).Exec(ctx, req.(*ExecProcessRequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _Shim_ResizePty_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(ResizePtyRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(ShimServer).ResizePty(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: "/containerd.runtime.linux.shim.v1.Shim/ResizePty",
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(ShimServer).ResizePty(ctx, req.(*ResizePtyRequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _Shim_CloseIO_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(CloseIORequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(ShimServer).CloseIO(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: "/containerd.runtime.linux.shim.v1.Shim/CloseIO",
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(ShimServer).CloseIO(ctx, req.(*CloseIORequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _Shim_ShimInfo_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(google_protobuf1.Empty)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(ShimServer).ShimInfo(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: "/containerd.runtime.linux.shim.v1.Shim/ShimInfo",
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(ShimServer).ShimInfo(ctx, req.(*google_protobuf1.Empty))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _Shim_Update_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(UpdateTaskRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(ShimServer).Update(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: "/containerd.runtime.linux.shim.v1.Shim/Update",
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(ShimServer).Update(ctx, req.(*UpdateTaskRequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _Shim_Wait_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(WaitRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(ShimServer).Wait(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: "/containerd.runtime.linux.shim.v1.Shim/Wait",
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(ShimServer).Wait(ctx, req.(*WaitRequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-var _Shim_serviceDesc = grpc.ServiceDesc{
-	ServiceName: "containerd.runtime.linux.shim.v1.Shim",
-	HandlerType: (*ShimServer)(nil),
-	Methods: []grpc.MethodDesc{
-		{
-			MethodName: "State",
-			Handler:    _Shim_State_Handler,
-		},
-		{
-			MethodName: "Create",
-			Handler:    _Shim_Create_Handler,
-		},
-		{
-			MethodName: "Start",
-			Handler:    _Shim_Start_Handler,
-		},
-		{
-			MethodName: "Delete",
-			Handler:    _Shim_Delete_Handler,
-		},
-		{
-			MethodName: "DeleteProcess",
-			Handler:    _Shim_DeleteProcess_Handler,
-		},
-		{
-			MethodName: "ListPids",
-			Handler:    _Shim_ListPids_Handler,
-		},
-		{
-			MethodName: "Pause",
-			Handler:    _Shim_Pause_Handler,
-		},
-		{
-			MethodName: "Resume",
-			Handler:    _Shim_Resume_Handler,
-		},
-		{
-			MethodName: "Checkpoint",
-			Handler:    _Shim_Checkpoint_Handler,
-		},
-		{
-			MethodName: "Kill",
-			Handler:    _Shim_Kill_Handler,
-		},
-		{
-			MethodName: "Exec",
-			Handler:    _Shim_Exec_Handler,
-		},
-		{
-			MethodName: "ResizePty",
-			Handler:    _Shim_ResizePty_Handler,
-		},
-		{
-			MethodName: "CloseIO",
-			Handler:    _Shim_CloseIO_Handler,
-		},
-		{
-			MethodName: "ShimInfo",
-			Handler:    _Shim_ShimInfo_Handler,
-		},
-		{
-			MethodName: "Update",
-			Handler:    _Shim_Update_Handler,
-		},
-		{
-			MethodName: "Wait",
-			Handler:    _Shim_Wait_Handler,
-		},
-	},
-	Streams:  []grpc.StreamDesc{},
-	Metadata: "github.com/containerd/containerd/linux/shim/v1/shim.proto",
-}
-
 func (m *CreateTaskRequest) Marshal() (dAtA []byte, err error) {
 	size := m.Size()
 	dAtA = make([]byte, size)
@@ -2151,6 +1577,280 @@ func valueToStringShim(v interface{}) string {
 	pv := reflect.Indirect(rv).Interface()
 	return fmt.Sprintf("*%v", pv)
 }
+
+type ShimService interface {
+	State(ctx context.Context, req *StateRequest) (*StateResponse, error)
+	Create(ctx context.Context, req *CreateTaskRequest) (*CreateTaskResponse, error)
+	Start(ctx context.Context, req *StartRequest) (*StartResponse, error)
+	Delete(ctx context.Context, req *google_protobuf1.Empty) (*DeleteResponse, error)
+	DeleteProcess(ctx context.Context, req *DeleteProcessRequest) (*DeleteResponse, error)
+	ListPids(ctx context.Context, req *ListPidsRequest) (*ListPidsResponse, error)
+	Pause(ctx context.Context, req *google_protobuf1.Empty) (*google_protobuf1.Empty, error)
+	Resume(ctx context.Context, req *google_protobuf1.Empty) (*google_protobuf1.Empty, error)
+	Checkpoint(ctx context.Context, req *CheckpointTaskRequest) (*google_protobuf1.Empty, error)
+	Kill(ctx context.Context, req *KillRequest) (*google_protobuf1.Empty, error)
+	Exec(ctx context.Context, req *ExecProcessRequest) (*google_protobuf1.Empty, error)
+	ResizePty(ctx context.Context, req *ResizePtyRequest) (*google_protobuf1.Empty, error)
+	CloseIO(ctx context.Context, req *CloseIORequest) (*google_protobuf1.Empty, error)
+	ShimInfo(ctx context.Context, req *google_protobuf1.Empty) (*ShimInfoResponse, error)
+	Update(ctx context.Context, req *UpdateTaskRequest) (*google_protobuf1.Empty, error)
+	Wait(ctx context.Context, req *WaitRequest) (*WaitResponse, error)
+}
+
+func RegisterShimService(srv *github_com_stevvooe_ttrpc.Server, svc ShimService) {
+	srv.Register("containerd.runtime.linux.shim.v1.Shim", map[string]github_com_stevvooe_ttrpc.Method{
+		"State": func(ctx context.Context, unmarshal func(interface{}) error) (interface{}, error) {
+			var req StateRequest
+			if err := unmarshal(&req); err != nil {
+				return nil, err
+			}
+			return svc.State(ctx, &req)
+		},
+		"Create": func(ctx context.Context, unmarshal func(interface{}) error) (interface{}, error) {
+			var req CreateTaskRequest
+			if err := unmarshal(&req); err != nil {
+				return nil, err
+			}
+			return svc.Create(ctx, &req)
+		},
+		"Start": func(ctx context.Context, unmarshal func(interface{}) error) (interface{}, error) {
+			var req StartRequest
+			if err := unmarshal(&req); err != nil {
+				return nil, err
+			}
+			return svc.Start(ctx, &req)
+		},
+		"Delete": func(ctx context.Context, unmarshal func(interface{}) error) (interface{}, error) {
+			var req google_protobuf1.Empty
+			if err := unmarshal(&req); err != nil {
+				return nil, err
+			}
+			return svc.Delete(ctx, &req)
+		},
+		"DeleteProcess": func(ctx context.Context, unmarshal func(interface{}) error) (interface{}, error) {
+			var req DeleteProcessRequest
+			if err := unmarshal(&req); err != nil {
+				return nil, err
+			}
+			return svc.DeleteProcess(ctx, &req)
+		},
+		"ListPids": func(ctx context.Context, unmarshal func(interface{}) error) (interface{}, error) {
+			var req ListPidsRequest
+			if err := unmarshal(&req); err != nil {
+				return nil, err
+			}
+			return svc.ListPids(ctx, &req)
+		},
+		"Pause": func(ctx context.Context, unmarshal func(interface{}) error) (interface{}, error) {
+			var req google_protobuf1.Empty
+			if err := unmarshal(&req); err != nil {
+				return nil, err
+			}
+			return svc.Pause(ctx, &req)
+		},
+		"Resume": func(ctx context.Context, unmarshal func(interface{}) error) (interface{}, error) {
+			var req google_protobuf1.Empty
+			if err := unmarshal(&req); err != nil {
+				return nil, err
+			}
+			return svc.Resume(ctx, &req)
+		},
+		"Checkpoint": func(ctx context.Context, unmarshal func(interface{}) error) (interface{}, error) {
+			var req CheckpointTaskRequest
+			if err := unmarshal(&req); err != nil {
+				return nil, err
+			}
+			return svc.Checkpoint(ctx, &req)
+		},
+		"Kill": func(ctx context.Context, unmarshal func(interface{}) error) (interface{}, error) {
+			var req KillRequest
+			if err := unmarshal(&req); err != nil {
+				return nil, err
+			}
+			return svc.Kill(ctx, &req)
+		},
+		"Exec": func(ctx context.Context, unmarshal func(interface{}) error) (interface{}, error) {
+			var req ExecProcessRequest
+			if err := unmarshal(&req); err != nil {
+				return nil, err
+			}
+			return svc.Exec(ctx, &req)
+		},
+		"ResizePty": func(ctx context.Context, unmarshal func(interface{}) error) (interface{}, error) {
+			var req ResizePtyRequest
+			if err := unmarshal(&req); err != nil {
+				return nil, err
+			}
+			return svc.ResizePty(ctx, &req)
+		},
+		"CloseIO": func(ctx context.Context, unmarshal func(interface{}) error) (interface{}, error) {
+			var req CloseIORequest
+			if err := unmarshal(&req); err != nil {
+				return nil, err
+			}
+			return svc.CloseIO(ctx, &req)
+		},
+		"ShimInfo": func(ctx context.Context, unmarshal func(interface{}) error) (interface{}, error) {
+			var req google_protobuf1.Empty
+			if err := unmarshal(&req); err != nil {
+				return nil, err
+			}
+			return svc.ShimInfo(ctx, &req)
+		},
+		"Update": func(ctx context.Context, unmarshal func(interface{}) error) (interface{}, error) {
+			var req UpdateTaskRequest
+			if err := unmarshal(&req); err != nil {
+				return nil, err
+			}
+			return svc.Update(ctx, &req)
+		},
+		"Wait": func(ctx context.Context, unmarshal func(interface{}) error) (interface{}, error) {
+			var req WaitRequest
+			if err := unmarshal(&req); err != nil {
+				return nil, err
+			}
+			return svc.Wait(ctx, &req)
+		},
+	})
+}
+
+type shimClient struct {
+	client *github_com_stevvooe_ttrpc.Client
+}
+
+func NewShimClient(client *github_com_stevvooe_ttrpc.Client) ShimService {
+	return &shimClient{
+		client: client,
+	}
+}
+
+func (c *shimClient) State(ctx context.Context, req *StateRequest) (*StateResponse, error) {
+	var resp StateResponse
+	if err := c.client.Call(ctx, "containerd.runtime.linux.shim.v1.Shim", "State", req, &resp); err != nil {
+		return nil, err
+	}
+	return &resp, nil
+}
+
+func (c *shimClient) Create(ctx context.Context, req *CreateTaskRequest) (*CreateTaskResponse, error) {
+	var resp CreateTaskResponse
+	if err := c.client.Call(ctx, "containerd.runtime.linux.shim.v1.Shim", "Create", req, &resp); err != nil {
+		return nil, err
+	}
+	return &resp, nil
+}
+
+func (c *shimClient) Start(ctx context.Context, req *StartRequest) (*StartResponse, error) {
+	var resp StartResponse
+	if err := c.client.Call(ctx, "containerd.runtime.linux.shim.v1.Shim", "Start", req, &resp); err != nil {
+		return nil, err
+	}
+	return &resp, nil
+}
+
+func (c *shimClient) Delete(ctx context.Context, req *google_protobuf1.Empty) (*DeleteResponse, error) {
+	var resp DeleteResponse
+	if err := c.client.Call(ctx, "containerd.runtime.linux.shim.v1.Shim", "Delete", req, &resp); err != nil {
+		return nil, err
+	}
+	return &resp, nil
+}
+
+func (c *shimClient) DeleteProcess(ctx context.Context, req *DeleteProcessRequest) (*DeleteResponse, error) {
+	var resp DeleteResponse
+	if err := c.client.Call(ctx, "containerd.runtime.linux.shim.v1.Shim", "DeleteProcess", req, &resp); err != nil {
+		return nil, err
+	}
+	return &resp, nil
+}
+
+func (c *shimClient) ListPids(ctx context.Context, req *ListPidsRequest) (*ListPidsResponse, error) {
+	var resp ListPidsResponse
+	if err := c.client.Call(ctx, "containerd.runtime.linux.shim.v1.Shim", "ListPids", req, &resp); err != nil {
+		return nil, err
+	}
+	return &resp, nil
+}
+
+func (c *shimClient) Pause(ctx context.Context, req *google_protobuf1.Empty) (*google_protobuf1.Empty, error) {
+	var resp google_protobuf1.Empty
+	if err := c.client.Call(ctx, "containerd.runtime.linux.shim.v1.Shim", "Pause", req, &resp); err != nil {
+		return nil, err
+	}
+	return &resp, nil
+}
+
+func (c *shimClient) Resume(ctx context.Context, req *google_protobuf1.Empty) (*google_protobuf1.Empty, error) {
+	var resp google_protobuf1.Empty
+	if err := c.client.Call(ctx, "containerd.runtime.linux.shim.v1.Shim", "Resume", req, &resp); err != nil {
+		return nil, err
+	}
+	return &resp, nil
+}
+
+func (c *shimClient) Checkpoint(ctx context.Context, req *CheckpointTaskRequest) (*google_protobuf1.Empty, error) {
+	var resp google_protobuf1.Empty
+	if err := c.client.Call(ctx, "containerd.runtime.linux.shim.v1.Shim", "Checkpoint", req, &resp); err != nil {
+		return nil, err
+	}
+	return &resp, nil
+}
+
+func (c *shimClient) Kill(ctx context.Context, req *KillRequest) (*google_protobuf1.Empty, error) {
+	var resp google_protobuf1.Empty
+	if err := c.client.Call(ctx, "containerd.runtime.linux.shim.v1.Shim", "Kill", req, &resp); err != nil {
+		return nil, err
+	}
+	return &resp, nil
+}
+
+func (c *shimClient) Exec(ctx context.Context, req *ExecProcessRequest) (*google_protobuf1.Empty, error) {
+	var resp google_protobuf1.Empty
+	if err := c.client.Call(ctx, "containerd.runtime.linux.shim.v1.Shim", "Exec", req, &resp); err != nil {
+		return nil, err
+	}
+	return &resp, nil
+}
+
+func (c *shimClient) ResizePty(ctx context.Context, req *ResizePtyRequest) (*google_protobuf1.Empty, error) {
+	var resp google_protobuf1.Empty
+	if err := c.client.Call(ctx, "containerd.runtime.linux.shim.v1.Shim", "ResizePty", req, &resp); err != nil {
+		return nil, err
+	}
+	return &resp, nil
+}
+
+func (c *shimClient) CloseIO(ctx context.Context, req *CloseIORequest) (*google_protobuf1.Empty, error) {
+	var resp google_protobuf1.Empty
+	if err := c.client.Call(ctx, "containerd.runtime.linux.shim.v1.Shim", "CloseIO", req, &resp); err != nil {
+		return nil, err
+	}
+	return &resp, nil
+}
+
+func (c *shimClient) ShimInfo(ctx context.Context, req *google_protobuf1.Empty) (*ShimInfoResponse, error) {
+	var resp ShimInfoResponse
+	if err := c.client.Call(ctx, "containerd.runtime.linux.shim.v1.Shim", "ShimInfo", req, &resp); err != nil {
+		return nil, err
+	}
+	return &resp, nil
+}
+
+func (c *shimClient) Update(ctx context.Context, req *UpdateTaskRequest) (*google_protobuf1.Empty, error) {
+	var resp google_protobuf1.Empty
+	if err := c.client.Call(ctx, "containerd.runtime.linux.shim.v1.Shim", "Update", req, &resp); err != nil {
+		return nil, err
+	}
+	return &resp, nil
+}
+
+func (c *shimClient) Wait(ctx context.Context, req *WaitRequest) (*WaitResponse, error) {
+	var resp WaitResponse
+	if err := c.client.Call(ctx, "containerd.runtime.linux.shim.v1.Shim", "Wait", req, &resp); err != nil {
+		return nil, err
+	}
+	return &resp, nil
+}
 func (m *CreateTaskRequest) Unmarshal(dAtA []byte) error {
 	l := len(dAtA)
 	iNdEx := 0

vendor.conf

@@ -41,3 +41,4 @@ github.com/boltdb/bolt e9cf4fae01b5a8ff89d0ec6b32f0d9c9f79aefdd
 google.golang.org/genproto d80a6e20e776b0b17a324d0ba1ab50a39c8e8944
 golang.org/x/text 19e51611da83d6be54ddafce4a4af510cb3e9ea4
 github.com/dmcgowan/go-tar 2e2c51242e8993c50445dab7c03c8e7febddd0cf
+github.com/stevvooe/ttrpc bdb2ab7a8169e485e39421e666e15a505e575fd2

vendor/github.com/stevvooe/ttrpc/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
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+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
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+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
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+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
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+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
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+      file or class name and description of purpose be included on the
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+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/github.com/stevvooe/ttrpc/README.md

@@ -0,0 +1,50 @@
+# ttrpc
+
+GRPC for low-memory environments.
+
+The existing grpc-go project requires a lot of memory overhead for importing
+packages and at runtime. While this is great for many services with low density
+requirements, this can be a problem when running a large number of services on
+a single machine or on a machine with a small amount of memory.
+
+Using the same GRPC definitions, this project reduces the binary size and
+protocol overhead required. We do this by eliding the `net/http`, `net/http2`
+and `grpc` package used by grpc replacing it with a lightweight framing
+protocol. The result are smaller binaries that use less resident memory with
+the same ease of use as GRPC.
+
+Please note that while this project supports generating either end of the
+protocol, the generated service definitions will be incompatible with regular
+GRPC services, as they do not speak the same protocol.
+
+# Usage
+
+Create a gogo vanity binary (see
+[`cmd/protoc-gen-gogottrpc/main.go`](cmd/protoc-gen-gogottrpc/main.go) for an
+example with the ttrpc plugin enabled.
+
+It's recommended to use [`protobuild`](https://github.com/stevvooe/protobuild)
+to build the protobufs for this project, but this will work with protoc
+directly, if required.
+
+# Differences from GRPC
+
+- The protocol stack has been replaced with a lighter protocol that doesn't
+  require http, http2 and tls.
+- The client and server interface are identical whereas in GRPC there is a
+  client and server interface that are different.
+- The Go stdlib context package is used instead.
+- No support for streams yet.
+
+# Status
+
+Very new. YMMV.
+
+TODO:
+
+- [X] Plumb error codes and GRPC status
+- [X] Remove use of any type and dependency on typeurl package
+- [X] Ensure that protocol can support streaming in the future
+- [ ] Document protocol layout
+- [ ] Add testing under concurrent load to ensure
+- [ ] Verify connection error handling

vendor/github.com/stevvooe/ttrpc/channel.go

@@ -0,0 +1,99 @@
+package ttrpc
+
+import (
+	"bufio"
+	"context"
+	"encoding/binary"
+	"io"
+
+	"github.com/pkg/errors"
+)
+
+const (
+	messageHeaderLength = 10
+	messageLengthMax    = 8 << 10
+)
+
+type messageType uint8
+
+const (
+	messageTypeRequest  messageType = 0x1
+	messageTypeResponse messageType = 0x2
+)
+
+// messageHeader represents the fixed-length message header of 10 bytes sent
+// with every request.
+type messageHeader struct {
+	Length   uint32      // length excluding this header. b[:4]
+	StreamID uint32      // identifies which request stream message is a part of. b[4:8]
+	Type     messageType // message type b[8]
+	Flags    uint8       // reserved          b[9]
+}
+
+func readMessageHeader(p []byte, r io.Reader) (messageHeader, error) {
+	_, err := io.ReadFull(r, p[:messageHeaderLength])
+	if err != nil {
+		return messageHeader{}, err
+	}
+
+	return messageHeader{
+		Length:   binary.BigEndian.Uint32(p[:4]),
+		StreamID: binary.BigEndian.Uint32(p[4:8]),
+		Type:     messageType(p[8]),
+		Flags:    p[9],
+	}, nil
+}
+
+func writeMessageHeader(w io.Writer, p []byte, mh messageHeader) error {
+	binary.BigEndian.PutUint32(p[:4], mh.Length)
+	binary.BigEndian.PutUint32(p[4:8], mh.StreamID)
+	p[8] = byte(mh.Type)
+	p[9] = mh.Flags
+
+	_, err := w.Write(p[:])
+	return err
+}
+
+type channel struct {
+	bw    *bufio.Writer
+	br    *bufio.Reader
+	hrbuf [messageHeaderLength]byte // avoid alloc when reading header
+	hwbuf [messageHeaderLength]byte
+}
+
+func newChannel(w io.Writer, r io.Reader) *channel {
+	return &channel{
+		bw: bufio.NewWriter(w),
+		br: bufio.NewReader(r),
+	}
+}
+
+func (ch *channel) recv(ctx context.Context, p []byte) (messageHeader, error) {
+	mh, err := readMessageHeader(ch.hrbuf[:], ch.br)
+	if err != nil {
+		return messageHeader{}, err
+	}
+
+	if mh.Length > uint32(len(p)) {
+		return messageHeader{}, errors.Wrapf(io.ErrShortBuffer, "message length %v over buffer size %v", mh.Length, len(p))
+	}
+
+	if _, err := io.ReadFull(ch.br, p[:mh.Length]); err != nil {
+		return messageHeader{}, errors.Wrapf(err, "failed reading message")
+	}
+
+	return mh, nil
+}
+
+func (ch *channel) send(ctx context.Context, streamID uint32, t messageType, p []byte) error {
+	if err := writeMessageHeader(ch.bw, ch.hwbuf[:], messageHeader{Length: uint32(len(p)), StreamID: streamID, Type: t}); err != nil {
+		return err
+	}
+
+	_, err := ch.bw.Write(p)
+	if err != nil {
+		return err
+	}
+
+	return ch.bw.Flush()
+}

vendor/github.com/stevvooe/ttrpc/client.go

@@ -0,0 +1,204 @@
+package ttrpc
+
+import (
+	"context"
+	"net"
+	"sync"
+	"sync/atomic"
+
+	"github.com/gogo/protobuf/proto"
+	"github.com/pkg/errors"
+	"google.golang.org/grpc/status"
+)
+
+type Client struct {
+	codec        codec
+	channel      *channel
+	requestID    uint32
+	sendRequests chan sendRequest
+	recvRequests chan recvRequest
+
+	closed    chan struct{}
+	closeOnce sync.Once
+	done      chan struct{}
+	err       error
+}
+
+func NewClient(conn net.Conn) *Client {
+	c := &Client{
+		codec:        codec{},
+		requestID:    1,
+		channel:      newChannel(conn, conn),
+		sendRequests: make(chan sendRequest),
+		recvRequests: make(chan recvRequest),
+		closed:       make(chan struct{}),
+		done:         make(chan struct{}),
+	}
+
+	go c.run()
+	return c
+}
+
+func (c *Client) Call(ctx context.Context, service, method string, req, resp interface{}) error {
+	payload, err := c.codec.Marshal(req)
+	if err != nil {
+		return err
+	}
+
+	requestID := atomic.AddUint32(&c.requestID, 2)
+	request := Request{
+		Service: service,
+		Method:  method,
+		Payload: payload,
+	}
+
+	if err := c.send(ctx, requestID, &request); err != nil {
+		return err
+	}
+
+	var response Response
+	if err := c.recv(ctx, requestID, &response); err != nil {
+		return err
+	}
+
+	if err := c.codec.Unmarshal(response.Payload, resp); err != nil {
+		return err
+	}
+
+	if response.Status == nil {
+		return errors.New("no status provided on response")
+	}
+
+	return status.ErrorProto(response.Status)
+}
+
+func (c *Client) Close() error {
+	c.closeOnce.Do(func() {
+		close(c.closed)
+	})
+
+	return nil
+}
+
+type sendRequest struct {
+	ctx context.Context
+	id  uint32
+	msg interface{}
+	err chan error
+}
+
+func (c *Client) send(ctx context.Context, id uint32, msg interface{}) error {
+	errs := make(chan error, 1)
+	select {
+	case c.sendRequests <- sendRequest{
+		ctx: ctx,
+		id:  id,
+		msg: msg,
+		err: errs,
+	}:
+	case <-ctx.Done():
+		return ctx.Err()
+	case <-c.done:
+		return c.err
+	}
+
+	select {
+	case err := <-errs:
+		return err
+	case <-ctx.Done():
+		return ctx.Err()
+	case <-c.done:
+		return c.err
+	}
+}
+
+type recvRequest struct {
+	id  uint32
+	msg interface{}
+	err chan error
+}
+
+func (c *Client) recv(ctx context.Context, id uint32, msg interface{}) error {
+	errs := make(chan error, 1)
+	select {
+	case c.recvRequests <- recvRequest{
+		id:  id,
+		msg: msg,
+		err: errs,
+	}:
+	case <-c.done:
+		return c.err
+	case <-ctx.Done():
+		return ctx.Err()
+	}
+
+	select {
+	case err := <-errs:
+		return err
+	case <-c.done:
+		return c.err
+	case <-ctx.Done():
+		return ctx.Err()
+	}
+}
+
+type received struct {
+	mh  messageHeader
+	p   []byte
+	err error
+}
+
+func (c *Client) run() {
+	defer close(c.done)
+	var (
+		waiters  = map[uint32]recvRequest{}
+		queued   = map[uint32]received{} // messages unmatched by waiter
+		incoming = make(chan received)
+	)
+
+	go func() {
+		// start one more goroutine to recv messages without blocking.
+		for {
+			var p [messageLengthMax]byte
+			mh, err := c.channel.recv(context.TODO(), p[:])
+			select {
+			case incoming <- received{
+				mh:  mh,
+				p:   p[:mh.Length],
+				err: err,
+			}:
+			case <-c.done:
+				return
+			}
+		}
+	}()
+
+	for {
+		select {
+		case req := <-c.sendRequests:
+			if p, err := proto.Marshal(req.msg.(proto.Message)); err != nil {
+				req.err <- err
+			} else {
+				req.err <- c.channel.send(req.ctx, req.id, messageTypeRequest, p)
+			}
+		case req := <-c.recvRequests:
+			if r, ok := queued[req.id]; ok {
+				req.err <- proto.Unmarshal(r.p, req.msg.(proto.Message))
+			}
+			waiters[req.id] = req
+		case r := <-incoming:
+			if r.err != nil {
+				c.err = r.err
+				return
+			}
+
+			if waiter, ok := waiters[r.mh.StreamID]; ok {
+				waiter.err <- proto.Unmarshal(r.p, waiter.msg.(proto.Message))
+			} else {
+				queued[r.mh.StreamID] = r
+			}
+		case <-c.closed:
+			return
+		}
+	}
+}

vendor/github.com/stevvooe/ttrpc/codec.go

@@ -0,0 +1,26 @@
+package ttrpc
+
+import (
+	"github.com/gogo/protobuf/proto"
+	"github.com/pkg/errors"
+)
+
+type codec struct{}
+
+func (c codec) Marshal(msg interface{}) ([]byte, error) {
+	switch v := msg.(type) {
+	case proto.Message:
+		return proto.Marshal(v)
+	default:
+		return nil, errors.Errorf("ttrpc: cannot marshal unknown type: %T", msg)
+	}
+}
+
+func (c codec) Unmarshal(p []byte, msg interface{}) error {
+	switch v := msg.(type) {
+	case proto.Message:
+		return proto.Unmarshal(p, v)
+	default:
+		return errors.Errorf("ttrpc: cannot unmarshal into unknown type: %T", msg)
+	}
+}

vendor/github.com/stevvooe/ttrpc/plugin/generator.go

@@ -0,0 +1,131 @@
+package plugin
+
+import (
+	"strings"
+
+	"github.com/gogo/protobuf/protoc-gen-gogo/descriptor"
+	"github.com/gogo/protobuf/protoc-gen-gogo/generator"
+)
+
+type ttrpcGenerator struct {
+	*generator.Generator
+	generator.PluginImports
+
+	typeurlPkg generator.Single
+	ttrpcPkg   generator.Single
+	contextPkg generator.Single
+}
+
+func init() {
+	generator.RegisterPlugin(new(ttrpcGenerator))
+}
+
+func (p *ttrpcGenerator) Name() string {
+	return "ttrpc"
+}
+
+func (p *ttrpcGenerator) Init(g *generator.Generator) {
+	p.Generator = g
+}
+
+func (p *ttrpcGenerator) Generate(file *generator.FileDescriptor) {
+	p.PluginImports = generator.NewPluginImports(p.Generator)
+	p.contextPkg = p.NewImport("context")
+	p.typeurlPkg = p.NewImport("github.com/containerd/typeurl")
+	p.ttrpcPkg = p.NewImport("github.com/stevvooe/ttrpc")
+
+	for _, service := range file.GetService() {
+		serviceName := service.GetName()
+		if pkg := file.GetPackage(); pkg != "" {
+			serviceName = pkg + "." + serviceName
+		}
+
+		p.genService(serviceName, service)
+	}
+}
+
+func (p *ttrpcGenerator) genService(fullName string, service *descriptor.ServiceDescriptorProto) {
+	serviceName := service.GetName() + "Service"
+	p.P()
+	p.P("type ", serviceName, " interface{")
+	p.In()
+	for _, method := range service.Method {
+		p.P(method.GetName(),
+			"(ctx ", p.contextPkg.Use(), ".Context, ",
+			"req *", p.typeName(method.GetInputType()), ") ",
+			"(*", p.typeName(method.GetOutputType()), ", error)")
+
+	}
+	p.Out()
+	p.P("}")
+
+	p.P()
+	// registration method
+	p.P("func Register", serviceName, "(srv *", p.ttrpcPkg.Use(), ".Server, svc ", serviceName, ") {")
+	p.In()
+	p.P(`srv.Register("`, fullName, `", map[string]`, p.ttrpcPkg.Use(), ".Method{")
+	p.In()
+	for _, method := range service.Method {
+		p.P(`"`, method.GetName(), `": `, `func(ctx context.Context, unmarshal func(interface{}) error) (interface{}, error) {`)
+		p.In()
+		p.P("var req ", p.typeName(method.GetInputType()))
+		p.P(`if err := unmarshal(&req); err != nil {`)
+		p.In()
+		p.P(`return nil, err`)
+		p.Out()
+		p.P(`}`)
+		p.P("return svc.", method.GetName(), "(ctx, &req)")
+		p.Out()
+		p.P("},")
+	}
+	p.Out()
+	p.P("})")
+	p.Out()
+	p.P("}")
+
+	clientType := service.GetName() + "Client"
+	clientStructType := strings.ToLower(clientType[:1]) + clientType[1:]
+	p.P()
+	p.P("type ", clientStructType, " struct{")
+	p.In()
+	p.P("client *", p.ttrpcPkg.Use(), ".Client")
+	p.Out()
+	p.P("}")
+	p.P()
+	p.P("func New", clientType, "(client *", p.ttrpcPkg.Use(), ".Client)", serviceName, "{")
+	p.In()
+	p.P("return &", clientStructType, "{")
+	p.In()
+	p.P("client: client,")
+	p.Out()
+	p.P("}")
+	p.Out()
+	p.P("}")
+	p.P()
+	for _, method := range service.Method {
+		p.P()
+		p.P("func (c *", clientStructType, ") ", method.GetName(),
+			"(ctx ", p.contextPkg.Use(), ".Context, ",
+			"req *", p.typeName(method.GetInputType()), ") ",
+			"(*", p.typeName(method.GetOutputType()), ", error) {")
+		p.In()
+		p.P("var resp ", p.typeName(method.GetOutputType()))
+		p.P("if err := c.client.Call(ctx, ", `"`+fullName+`", `, `"`+method.GetName()+`"`, ", req, &resp); err != nil {")
+		p.In()
+		p.P("return nil, err")
+		p.Out()
+		p.P("}")
+		p.P("return &resp, nil")
+		p.Out()
+		p.P("}")
+	}
+}
+
+func (p *ttrpcGenerator) objectNamed(name string) generator.Object {
+	p.Generator.RecordTypeUse(name)
+	return p.Generator.ObjectNamed(name)
+}
+
+func (p *ttrpcGenerator) typeName(str string) string {
+	return p.Generator.TypeName(p.objectNamed(str))
+}

vendor/github.com/stevvooe/ttrpc/server.go

@@ -0,0 +1,155 @@
+package ttrpc
+
+import (
+	"context"
+	"net"
+
+	"github.com/containerd/containerd/log"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+)
+
+type Server struct {
+	services *serviceSet
+	codec    codec
+}
+
+func NewServer() *Server {
+	return &Server{
+		services: newServiceSet(),
+	}
+}
+
+func (s *Server) Register(name string, methods map[string]Method) {
+	s.services.register(name, methods)
+}
+
+func (s *Server) Shutdown(ctx context.Context) error {
+	// TODO(stevvooe): Wait on connection shutdown.
+	return nil
+}
+
+func (s *Server) Serve(l net.Listener) error {
+	for {
+		conn, err := l.Accept()
+		if err != nil {
+			log.L.WithError(err).Error("failed accept")
+			continue
+		}
+
+		go s.handleConn(conn)
+	}
+
+	return nil
+}
+
+func (s *Server) handleConn(conn net.Conn) {
+	defer conn.Close()
+
+	type (
+		request struct {
+			id  uint32
+			req *Request
+		}
+
+		response struct {
+			id   uint32
+			resp *Response
+		}
+	)
+
+	var (
+		ch          = newChannel(conn, conn)
+		ctx, cancel = context.WithCancel(context.Background())
+		responses   = make(chan response)
+		requests    = make(chan request)
+		recvErr     = make(chan error, 1)
+		done        = make(chan struct{})
+	)
+
+	defer cancel()
+	defer close(done)
+
+	go func() {
+		defer close(recvErr)
+		var p [messageLengthMax]byte
+		for {
+			mh, err := ch.recv(ctx, p[:])
+			if err != nil {
+				recvErr <- err
+				return
+			}
+
+			if mh.Type != messageTypeRequest {
+				// we must ignore this for future compat.
+				continue
+			}
+
+			var req Request
+			if err := s.codec.Unmarshal(p[:mh.Length], &req); err != nil {
+				recvErr <- err
+				return
+			}
+
+			if mh.StreamID%2 != 1 {
+				// enforce odd client initiated identifiers.
+				select {
+				case responses <- response{
+					// even though we've had an invalid stream id, we send it
+					// back on the same stream id so the client knows which
+					// stream id was bad.
+					id: mh.StreamID,
+					resp: &Response{
+						Status: status.New(codes.InvalidArgument, "StreamID must be odd for client initiated streams").Proto(),
+					},
+				}:
+				case <-done:
+				}
+
+				continue
+			}
+
+			select {
+			case requests <- request{
+				id:  mh.StreamID,
+				req: &req,
+			}:
+			case <-done:
+			}
+		}
+	}()
+
+	for {
+		select {
+		case request := <-requests:
+			go func(id uint32) {
+				p, status := s.services.call(ctx, request.req.Service, request.req.Method, request.req.Payload)
+				resp := &Response{
+					Status:  status.Proto(),
+					Payload: p,
+				}
+
+				select {
+				case responses <- response{
+					id:   id,
+					resp: resp,
+				}:
+				case <-done:
+				}
+			}(request.id)
+		case response := <-responses:
+			p, err := s.codec.Marshal(response.resp)
+			if err != nil {
+				log.L.WithError(err).Error("failed marshaling response")
+				return
+			}
+			if err := ch.send(ctx, response.id, messageTypeResponse, p); err != nil {
+				log.L.WithError(err).Error("failed sending message on channel")
+				return
+			}
+		case err := <-recvErr:
+			log.L.WithError(err).Error("error receiving message")
+			return
+		}
+	}
+}

vendor/github.com/stevvooe/ttrpc/services.go

@@ -0,0 +1,134 @@
+package ttrpc
+
+import (
+	"context"
+	"io"
+	"os"
+	"path"
+
+	"github.com/gogo/protobuf/proto"
+	"github.com/pkg/errors"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+)
+
+type Method func(ctx context.Context, unmarshal func(interface{}) error) (interface{}, error)
+
+type ServiceDesc struct {
+	Methods map[string]Method
+
+	// TODO(stevvooe): Add stream support.
+}
+
+type serviceSet struct {
+	services map[string]ServiceDesc
+}
+
+func newServiceSet() *serviceSet {
+	return &serviceSet{
+		services: make(map[string]ServiceDesc),
+	}
+}
+
+func (s *serviceSet) register(name string, methods map[string]Method) {
+	if _, ok := s.services[name]; ok {
+		panic(errors.Errorf("duplicate service %v registered", name))
+	}
+
+	s.services[name] = ServiceDesc{
+		Methods: methods,
+	}
+}
+
+func (s *serviceSet) call(ctx context.Context, serviceName, methodName string, p []byte) ([]byte, *status.Status) {
+	p, err := s.dispatch(ctx, serviceName, methodName, p)
+	st, ok := status.FromError(err)
+	if !ok {
+		st = status.New(convertCode(err), err.Error())
+	}
+
+	return p, st
+}
+
+func (s *serviceSet) dispatch(ctx context.Context, serviceName, methodName string, p []byte) ([]byte, error) {
+	method, err := s.resolve(serviceName, methodName)
+	if err != nil {
+		return nil, err
+	}
+
+	unmarshal := func(obj interface{}) error {
+		switch v := obj.(type) {
+		case proto.Message:
+			if err := proto.Unmarshal(p, v); err != nil {
+				return status.Errorf(codes.Internal, "ttrpc: error unmarshaling payload: %v", err.Error())
+			}
+		default:
+			return status.Errorf(codes.Internal, "ttrpc: error unsupported request type: %T", v)
+		}
+		return nil
+	}
+
+	resp, err := method(ctx, unmarshal)
+	if err != nil {
+		return nil, err
+	}
+
+	switch v := resp.(type) {
+	case proto.Message:
+		r, err := proto.Marshal(v)
+		if err != nil {
+			return nil, status.Errorf(codes.Internal, "ttrpc: error marshaling payload: %v", err.Error())
+		}
+
+		return r, nil
+	default:
+		return nil, status.Errorf(codes.Internal, "ttrpc: error unsupported response type: %T", v)
+	}
+}
+
+func (s *serviceSet) resolve(service, method string) (Method, error) {
+	srv, ok := s.services[service]
+	if !ok {
+		return nil, status.Errorf(codes.NotFound, "service %v", service)
+	}
+
+	mthd, ok := srv.Methods[method]
+	if !ok {
+		return nil, status.Errorf(codes.NotFound, "method %v", method)
+	}
+
+	return mthd, nil
+}
+
+// convertCode maps stdlib go errors into grpc space.
+//
+// This is ripped from the grpc-go code base.
+func convertCode(err error) codes.Code {
+	switch err {
+	case nil:
+		return codes.OK
+	case io.EOF:
+		return codes.OutOfRange
+	case io.ErrClosedPipe, io.ErrNoProgress, io.ErrShortBuffer, io.ErrShortWrite, io.ErrUnexpectedEOF:
+		return codes.FailedPrecondition
+	case os.ErrInvalid:
+		return codes.InvalidArgument
+	case context.Canceled:
+		return codes.Canceled
+	case context.DeadlineExceeded:
+		return codes.DeadlineExceeded
+	}
+	switch {
+	case os.IsExist(err):
+		return codes.AlreadyExists
+	case os.IsNotExist(err):
+		return codes.NotFound
+	case os.IsPermission(err):
+		return codes.PermissionDenied
+	}
+	return codes.Unknown
+}
+
+func fullPath(service, method string) string {
+	return "/" + path.Join("/", service, method)
+}

vendor/github.com/stevvooe/ttrpc/types.go

@@ -0,0 +1,26 @@
+package ttrpc
+
+import (
+	"fmt"
+
+	spb "google.golang.org/genproto/googleapis/rpc/status"
+)
+
+type Request struct {
+	Service string `protobuf:"bytes,1,opt,name=service,proto3"`
+	Method  string `protobuf:"bytes,2,opt,name=method,proto3"`
+	Payload []byte `protobuf:"bytes,3,opt,name=payload,proto3"`
+}
+
+func (r *Request) Reset()         { *r = Request{} }
+func (r *Request) String() string { return fmt.Sprintf("%+#v", r) }
+func (r *Request) ProtoMessage()  {}
+
+type Response struct {
+	Status  *spb.Status `protobuf:"bytes,1,opt,name=status,proto3"`
+	Payload []byte      `protobuf:"bytes,2,opt,name=payload,proto3"`
+}
+
+func (r *Response) Reset()         { *r = Response{} }
+func (r *Response) String() string { return fmt.Sprintf("%+#v", r) }
+func (r *Response) ProtoMessage()  {}