factory: set guest time after resuming

We might have paused a guest for a long time so we need to sync
its time.

Fixes:#951
Signed-off-by: Peng Tao <bergwolf@gmail.com>

virtcontainers/agent.go

@@ -8,6 +8,7 @@ package virtcontainers
 import (
 	"fmt"
 	"syscall"
+	"time"
 
 	"github.com/kata-containers/agent/protocols/grpc"
 	"github.com/kata-containers/runtime/virtcontainers/pkg/types"
@@ -246,4 +247,7 @@ type agent interface {
 
 	// getGuestDetails will tell the agent to get some information of guest
 	getGuestDetails(*grpc.GuestDetailsRequest) (*grpc.GuestDetailsResponse, error)
+
+	// setGuestDateTime asks the agent to set guest time to the provided one
+	setGuestDateTime(time.Time) error
 }

virtcontainers/factory/factory.go

@@ -248,6 +248,12 @@ func (f *factory) GetVM(ctx context.Context, config vc.VMConfig) (*vc.VM, error)
 		return nil, err
 	}
 
+	// sync guest time since we might have paused it for a long time.
+	err = vm.SyncTime()
+	if err != nil {
+		return nil, err
+	}
+
 	online := false
 	baseConfig := f.base.Config().HypervisorConfig
 	if baseConfig.NumVCPUs < hypervisorConfig.NumVCPUs {

virtcontainers/hyperstart_agent.go

@@ -1000,3 +1000,8 @@ func (h *hyper) getGuestDetails(*grpc.GuestDetailsRequest) (*grpc.GuestDetailsRe
 	// hyperstart-agent does not support getGuestDetails
 	return nil, nil
 }
+
+func (h *hyper) setGuestDateTime(time.Time) error {
+	// hyperstart-agent does not support setGuestDateTime
+	return nil
+}

virtcontainers/kata_agent.go

@@ -1490,6 +1490,9 @@ func (k *kataAgent) installReqFunc(c *kataclient.AgentClient) {
 	k.reqHandlers["grpc.GuestDetailsRequest"] = func(ctx context.Context, req interface{}, opts ...golangGrpc.CallOption) (interface{}, error) {
 		return k.client.GetGuestDetails(ctx, req.(*grpc.GuestDetailsRequest), opts...)
 	}
+	k.reqHandlers["grpc.SetGuestDateTimeRequest"] = func(ctx context.Context, req interface{}, opts ...golangGrpc.CallOption) (interface{}, error) {
+		return k.client.SetGuestDateTime(ctx, req.(*grpc.SetGuestDateTimeRequest), opts...)
+	}
 }
 
 func (k *kataAgent) sendReq(request interface{}) (interface{}, error) {
@@ -1563,6 +1566,15 @@ func (k *kataAgent) getGuestDetails(req *grpc.GuestDetailsRequest) (*grpc.GuestD
 	return resp.(*grpc.GuestDetailsResponse), nil
 }
 
+func (k *kataAgent) setGuestDateTime(tv time.Time) error {
+	_, err := k.sendReq(&grpc.SetGuestDateTimeRequest{
+		Sec:  tv.Unix(),
+		Usec: int64(tv.Nanosecond() / 1e3),
+	})
+
+	return err
+}
+
 func (k *kataAgent) convertToKataAgentIPFamily(ipFamily int) aTypes.IPFamily {
 	switch ipFamily {
 	case netlink.FAMILY_V4:

virtcontainers/kata_agent_test.go

@@ -243,6 +243,10 @@ func (p *gRPCProxy) GetGuestDetails(ctx context.Context, req *pb.GuestDetailsReq
 	return &pb.GuestDetailsResponse{}, nil
 }
 
+func (p *gRPCProxy) SetGuestDateTime(ctx context.Context, req *pb.SetGuestDateTimeRequest) (*gpb.Empty, error) {
+	return &gpb.Empty{}, nil
+}
+
 func gRPCRegister(s *grpc.Server, srv interface{}) {
 	switch g := srv.(type) {
 	case *gRPCProxy:
@@ -262,6 +266,7 @@ var reqList = []interface{}{
 	&pb.CheckRequest{},
 	&pb.WaitProcessRequest{},
 	&pb.StatsContainerRequest{},
+	&pb.SetGuestDateTimeRequest{},
 }
 
 func TestKataAgentSendReq(t *testing.T) {

virtcontainers/noop_agent.go

@@ -7,6 +7,7 @@ package virtcontainers
 
 import (
 	"syscall"
+	"time"
 
 	"github.com/kata-containers/agent/protocols/grpc"
 	"github.com/kata-containers/runtime/virtcontainers/pkg/types"
@@ -203,3 +204,8 @@ func (n *noopAgent) setProxy(sandbox *Sandbox, proxy proxy, pid int, url string)
 func (n *noopAgent) getGuestDetails(*grpc.GuestDetailsRequest) (*grpc.GuestDetailsResponse, error) {
 	return nil, nil
 }
+
+// setGuestDateTime is the Noop agent guest time setter. It does nothing.
+func (n *noopAgent) setGuestDateTime(time.Time) error {
+	return nil
+}

virtcontainers/vm.go

@@ -9,6 +9,7 @@ import (
 	"context"
 	"os"
 	"path/filepath"
+	"time"
 
 	"github.com/kata-containers/runtime/virtcontainers/pkg/uuid"
 	"github.com/sirupsen/logrus"
@@ -296,6 +297,13 @@ func (v *VM) ReseedRNG() error {
 	return v.agent.reseedRNG(data)
 }
 
+// SyncTime syncs guest time with host time.
+func (v *VM) SyncTime() error {
+	now := time.Now()
+	v.logger().WithField("time", now).Infof("sync guest time")
+	return v.agent.setGuestDateTime(now)
+}
+
 func (v *VM) assignSandbox(s *Sandbox) error {
 	// add vm symlinks
 	// - link vm socket from sandbox dir (/run/vc/vm/sbid/<kata.sock>) to vm dir (/run/vc/vm/vmid/<kata.sock>)