diff options
Diffstat (limited to 'vendor/github.com/checkpoint-restore/go-criu/main.go')
-rw-r--r-- | vendor/github.com/checkpoint-restore/go-criu/main.go | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/vendor/github.com/checkpoint-restore/go-criu/main.go b/vendor/github.com/checkpoint-restore/go-criu/main.go new file mode 100644 index 000000000..cf94c376e --- /dev/null +++ b/vendor/github.com/checkpoint-restore/go-criu/main.go @@ -0,0 +1,250 @@ +package criu + +import ( + "errors" + "fmt" + "os" + "os/exec" + "strconv" + "syscall" + + "github.com/checkpoint-restore/go-criu/rpc" + "github.com/golang/protobuf/proto" +) + +// Criu struct +type Criu struct { + swrkCmd *exec.Cmd + swrkSk *os.File +} + +// MakeCriu returns the Criu object required for most operations +func MakeCriu() *Criu { + return &Criu{} +} + +// Prepare sets up everything for the RPC communication to CRIU +func (c *Criu) Prepare() error { + fds, err := syscall.Socketpair(syscall.AF_LOCAL, syscall.SOCK_SEQPACKET, 0) + if err != nil { + return err + } + + cln := os.NewFile(uintptr(fds[0]), "criu-xprt-cln") + syscall.CloseOnExec(fds[0]) + srv := os.NewFile(uintptr(fds[1]), "criu-xprt-srv") + defer srv.Close() + + args := []string{"swrk", strconv.Itoa(fds[1])} + cmd := exec.Command("criu", args...) + + err = cmd.Start() + if err != nil { + cln.Close() + return err + } + + c.swrkCmd = cmd + c.swrkSk = cln + + return nil +} + +// Cleanup cleans up +func (c *Criu) Cleanup() { + if c.swrkCmd != nil { + c.swrkSk.Close() + c.swrkSk = nil + c.swrkCmd.Wait() + c.swrkCmd = nil + } +} + +func (c *Criu) sendAndRecv(reqB []byte) ([]byte, int, error) { + cln := c.swrkSk + _, err := cln.Write(reqB) + if err != nil { + return nil, 0, err + } + + respB := make([]byte, 2*4096) + n, err := cln.Read(respB) + if err != nil { + return nil, 0, err + } + + return respB, n, nil +} + +func (c *Criu) doSwrk(reqType rpc.CriuReqType, opts *rpc.CriuOpts, nfy Notify) error { + resp, err := c.doSwrkWithResp(reqType, opts, nfy) + if err != nil { + return err + } + respType := resp.GetType() + if respType != reqType { + return errors.New("unexpected responce") + } + + return nil +} + +func (c *Criu) doSwrkWithResp(reqType rpc.CriuReqType, opts *rpc.CriuOpts, nfy Notify) (*rpc.CriuResp, error) { + var resp *rpc.CriuResp + + req := rpc.CriuReq{ + Type: &reqType, + Opts: opts, + } + + if nfy != nil { + opts.NotifyScripts = proto.Bool(true) + } + + if c.swrkCmd == nil { + err := c.Prepare() + if err != nil { + return nil, err + } + + defer c.Cleanup() + } + + for { + reqB, err := proto.Marshal(&req) + if err != nil { + return nil, err + } + + respB, respS, err := c.sendAndRecv(reqB) + if err != nil { + return nil, err + } + + resp = &rpc.CriuResp{} + err = proto.Unmarshal(respB[:respS], resp) + if err != nil { + return nil, err + } + + if !resp.GetSuccess() { + return resp, fmt.Errorf("operation failed (msg:%s err:%d)", + resp.GetCrErrmsg(), resp.GetCrErrno()) + } + + respType := resp.GetType() + if respType != rpc.CriuReqType_NOTIFY { + break + } + if nfy == nil { + return resp, errors.New("unexpected notify") + } + + notify := resp.GetNotify() + switch notify.GetScript() { + case "pre-dump": + err = nfy.PreDump() + case "post-dump": + err = nfy.PostDump() + case "pre-restore": + err = nfy.PreRestore() + case "post-restore": + err = nfy.PostRestore(notify.GetPid()) + case "network-lock": + err = nfy.NetworkLock() + case "network-unlock": + err = nfy.NetworkUnlock() + case "setup-namespaces": + err = nfy.SetupNamespaces(notify.GetPid()) + case "post-setup-namespaces": + err = nfy.PostSetupNamespaces() + case "post-resume": + err = nfy.PostResume() + default: + err = nil + } + + if err != nil { + return resp, err + } + + req = rpc.CriuReq{ + Type: &respType, + NotifySuccess: proto.Bool(true), + } + } + + return resp, nil +} + +// Dump dumps a process +func (c *Criu) Dump(opts rpc.CriuOpts, nfy Notify) error { + return c.doSwrk(rpc.CriuReqType_DUMP, &opts, nfy) +} + +// Restore restores a process +func (c *Criu) Restore(opts rpc.CriuOpts, nfy Notify) error { + return c.doSwrk(rpc.CriuReqType_RESTORE, &opts, nfy) +} + +// PreDump does a pre-dump +func (c *Criu) PreDump(opts rpc.CriuOpts, nfy Notify) error { + return c.doSwrk(rpc.CriuReqType_PRE_DUMP, &opts, nfy) +} + +// StartPageServer starts the page server +func (c *Criu) StartPageServer(opts rpc.CriuOpts) error { + return c.doSwrk(rpc.CriuReqType_PAGE_SERVER, &opts, nil) +} + +// StartPageServerChld starts the page server and returns PID and port +func (c *Criu) StartPageServerChld(opts rpc.CriuOpts) (int, int, error) { + resp, err := c.doSwrkWithResp(rpc.CriuReqType_PAGE_SERVER_CHLD, &opts, nil) + if err != nil { + return 0, 0, err + } + + return int(resp.Ps.GetPid()), int(resp.Ps.GetPort()), nil +} + +// GetCriuVersion executes the VERSION RPC call and returns the version +// as an integer. Major * 10000 + Minor * 100 + SubLevel +func (c *Criu) GetCriuVersion() (int, error) { + resp, err := c.doSwrkWithResp(rpc.CriuReqType_VERSION, nil, nil) + if err != nil { + return 0, err + } + + if resp.GetType() != rpc.CriuReqType_VERSION { + return 0, fmt.Errorf("Unexpected CRIU RPC response") + } + + version := int(*resp.GetVersion().Major) * 10000 + version += int(*resp.GetVersion().Minor) * 100 + if resp.GetVersion().Sublevel != nil { + version += int(*resp.GetVersion().Sublevel) + } + + if resp.GetVersion().Gitid != nil { + // taken from runc: if it is a git release -> increase minor by 1 + version -= (version % 100) + version += 100 + } + + return version, nil +} + +// IsCriuAtLeast checks if the version is at least the same +// as the parameter version +func (c *Criu) IsCriuAtLeast(version int) (bool, error) { + criuVersion, err := c.GetCriuVersion() + if err != nil { + return false, err + } + + if criuVersion >= version { + return true, nil + } + + return false, nil +} |