package driver import ( "bytes" "context" "encoding/json" "fmt" "log" "net" "os" "os/exec" "path/filepath" "regexp" "runtime" "strconv" "strings" "syscall" "time" "github.com/hashicorp/go-plugin" "github.com/hashicorp/go-version" "github.com/hashicorp/nomad/client/allocdir" "github.com/hashicorp/nomad/client/config" "github.com/hashicorp/nomad/client/driver/env" "github.com/hashicorp/nomad/client/driver/executor" dstructs "github.com/hashicorp/nomad/client/driver/structs" cstructs "github.com/hashicorp/nomad/client/structs" "github.com/hashicorp/nomad/helper" "github.com/hashicorp/nomad/helper/fields" "github.com/hashicorp/nomad/nomad/structs" "github.com/mitchellh/mapstructure" ) var ( reRktVersion = regexp.MustCompile(`rkt [vV]ersion[:]? (\d[.\d]+)`) reAppcVersion = regexp.MustCompile(`appc [vV]ersion[:]? (\d[.\d]+)`) ) const ( // minRktVersion is the earliest supported version of rkt. rkt added support // for CPU and memory isolators in 0.14.0. We cannot support an earlier // version to maintain an uniform interface across all drivers minRktVersion = "1.0.0" // The key populated in the Node Attributes to indicate the presence of the // Rkt driver rktDriverAttr = "driver.rkt" // rktVolumesConfigOption is the key for enabling the use of custom // bind volumes. rktVolumesConfigOption = "rkt.volumes.enabled" rktVolumesConfigDefault = true // rktCmd is the command rkt is installed as. rktCmd = "rkt" ) // RktDriver is a driver for running images via Rkt // We attempt to chose sane defaults for now, with more configuration available // planned in the future type RktDriver struct { DriverContext // A tri-state boolean to know if the fingerprinting has happened and // whether it has been successful fingerprintSuccess *bool } type RktDriverConfig struct { ImageName string `mapstructure:"image"` Command string `mapstructure:"command"` Args []string `mapstructure:"args"` TrustPrefix string `mapstructure:"trust_prefix"` DNSServers []string `mapstructure:"dns_servers"` // DNS Server for containers DNSSearchDomains []string `mapstructure:"dns_search_domains"` // DNS Search domains for containers Net []string `mapstructure:"net"` // Networks for the containers PortMapRaw []map[string]string `mapstructure:"port_map"` // PortMap map[string]string `mapstructure:"-"` // A map of host port and the port name defined in the image manifest file Volumes []string `mapstructure:"volumes"` // Host-Volumes to mount in, syntax: /path/to/host/directory:/destination/path/in/container[:readOnly] InsecureOptions []string `mapstructure:"insecure_options"` // list of args for --insecure-options NoOverlay bool `mapstructure:"no_overlay"` // disable overlayfs for rkt run Debug bool `mapstructure:"debug"` // Enable debug option for rkt command } // rktHandle is returned from Start/Open as a handle to the PID type rktHandle struct { uuid string env *env.TaskEnv taskDir *allocdir.TaskDir pluginClient *plugin.Client executorPid int executor executor.Executor logger *log.Logger killTimeout time.Duration maxKillTimeout time.Duration waitCh chan *dstructs.WaitResult doneCh chan struct{} } // rktPID is a struct to map the pid running the process to the vm image on // disk type rktPID struct { UUID string PluginConfig *PluginReattachConfig ExecutorPid int KillTimeout time.Duration MaxKillTimeout time.Duration } // NewRktDriver is used to create a new exec driver func NewRktDriver(ctx *DriverContext) Driver { return &RktDriver{DriverContext: *ctx} } func (d *RktDriver) FSIsolation() cstructs.FSIsolation { return cstructs.FSIsolationImage } // Validate is used to validate the driver configuration func (d *RktDriver) Validate(config map[string]interface{}) error { fd := &fields.FieldData{ Raw: config, Schema: map[string]*fields.FieldSchema{ "image": &fields.FieldSchema{ Type: fields.TypeString, Required: true, }, "command": &fields.FieldSchema{ Type: fields.TypeString, }, "args": &fields.FieldSchema{ Type: fields.TypeArray, }, "trust_prefix": &fields.FieldSchema{ Type: fields.TypeString, }, "dns_servers": &fields.FieldSchema{ Type: fields.TypeArray, }, "dns_search_domains": &fields.FieldSchema{ Type: fields.TypeArray, }, "net": &fields.FieldSchema{ Type: fields.TypeArray, }, "port_map": &fields.FieldSchema{ Type: fields.TypeArray, }, "debug": &fields.FieldSchema{ Type: fields.TypeBool, }, "volumes": &fields.FieldSchema{ Type: fields.TypeArray, }, "no_overlay": &fields.FieldSchema{ Type: fields.TypeBool, }, "insecure_options": &fields.FieldSchema{ Type: fields.TypeArray, }, }, } if err := fd.Validate(); err != nil { return err } return nil } func (d *RktDriver) Abilities() DriverAbilities { return DriverAbilities{ SendSignals: false, Exec: true, } } func (d *RktDriver) Fingerprint(cfg *config.Config, node *structs.Node) (bool, error) { // Only enable if we are root when running on non-windows systems. if runtime.GOOS != "windows" && syscall.Geteuid() != 0 { if d.fingerprintSuccess == nil || *d.fingerprintSuccess { d.logger.Printf("[DEBUG] driver.rkt: must run as root user, disabling") } delete(node.Attributes, rktDriverAttr) d.fingerprintSuccess = helper.BoolToPtr(false) return false, nil } outBytes, err := exec.Command(rktCmd, "version").Output() if err != nil { delete(node.Attributes, rktDriverAttr) d.fingerprintSuccess = helper.BoolToPtr(false) return false, nil } out := strings.TrimSpace(string(outBytes)) rktMatches := reRktVersion.FindStringSubmatch(out) appcMatches := reAppcVersion.FindStringSubmatch(out) if len(rktMatches) != 2 || len(appcMatches) != 2 { delete(node.Attributes, rktDriverAttr) d.fingerprintSuccess = helper.BoolToPtr(false) return false, fmt.Errorf("Unable to parse Rkt version string: %#v", rktMatches) } node.Attributes[rktDriverAttr] = "1" node.Attributes["driver.rkt.version"] = rktMatches[1] node.Attributes["driver.rkt.appc.version"] = appcMatches[1] minVersion, _ := version.NewVersion(minRktVersion) currentVersion, _ := version.NewVersion(node.Attributes["driver.rkt.version"]) if currentVersion.LessThan(minVersion) { // Do not allow ancient rkt versions d.logger.Printf("[WARN] driver.rkt: please upgrade rkt to a version >= %s", minVersion) node.Attributes[rktDriverAttr] = "0" } // Advertise if this node supports rkt volumes if d.config.ReadBoolDefault(rktVolumesConfigOption, rktVolumesConfigDefault) { node.Attributes["driver."+rktVolumesConfigOption] = "1" } d.fingerprintSuccess = helper.BoolToPtr(true) return true, nil } func (d *RktDriver) Periodic() (bool, time.Duration) { return true, 15 * time.Second } func (d *RktDriver) Prestart(ctx *ExecContext, task *structs.Task) (*PrestartResponse, error) { return nil, nil } // Run an existing Rkt image. func (d *RktDriver) Start(ctx *ExecContext, task *structs.Task) (*StartResponse, error) { var driverConfig RktDriverConfig if err := mapstructure.WeakDecode(task.Config, &driverConfig); err != nil { return nil, err } driverConfig.PortMap = mapMergeStrStr(driverConfig.PortMapRaw...) // ACI image img := driverConfig.ImageName // Global arguments given to both prepare and run-prepared globalArgs := make([]string, 0, 50) // Add debug option to rkt command. debug := driverConfig.Debug // Add the given trust prefix trustPrefix := driverConfig.TrustPrefix insecure := false if trustPrefix != "" { var outBuf, errBuf bytes.Buffer cmd := exec.Command(rktCmd, "trust", "--skip-fingerprint-review=true", fmt.Sprintf("--prefix=%s", trustPrefix), fmt.Sprintf("--debug=%t", debug)) cmd.Stdout = &outBuf cmd.Stderr = &errBuf if err := cmd.Run(); err != nil { return nil, fmt.Errorf("Error running rkt trust: %s\n\nOutput: %s\n\nError: %s", err, outBuf.String(), errBuf.String()) } d.logger.Printf("[DEBUG] driver.rkt: added trust prefix: %q", trustPrefix) } else { // Disble signature verification if the trust command was not run. insecure = true } // if we have a selective insecure_options, prefer them // insecure options are rkt's global argument, so we do this before the actual "run" if len(driverConfig.InsecureOptions) > 0 { globalArgs = append(globalArgs, fmt.Sprintf("--insecure-options=%s", strings.Join(driverConfig.InsecureOptions, ","))) } else if insecure { globalArgs = append(globalArgs, "--insecure-options=all") } // debug is rkt's global argument, so add it before the actual "run" globalArgs = append(globalArgs, fmt.Sprintf("--debug=%t", debug)) prepareArgs := make([]string, 0, 50) runArgs := make([]string, 0, 50) prepareArgs = append(prepareArgs, globalArgs...) prepareArgs = append(prepareArgs, "prepare") runArgs = append(runArgs, globalArgs...) runArgs = append(runArgs, "run-prepared") // disable overlayfs if driverConfig.NoOverlay { prepareArgs = append(prepareArgs, "--no-overlay=true") } // Convert underscores to dashes in task names for use in volume names #2358 sanitizedName := strings.Replace(task.Name, "_", "-", -1) // Mount /alloc allocVolName := fmt.Sprintf("%s-%s-alloc", d.DriverContext.allocID, sanitizedName) prepareArgs = append(prepareArgs, fmt.Sprintf("--volume=%s,kind=host,source=%s", allocVolName, ctx.TaskDir.SharedAllocDir)) prepareArgs = append(prepareArgs, fmt.Sprintf("--mount=volume=%s,target=%s", allocVolName, allocdir.SharedAllocContainerPath)) // Mount /local localVolName := fmt.Sprintf("%s-%s-local", d.DriverContext.allocID, sanitizedName) prepareArgs = append(prepareArgs, fmt.Sprintf("--volume=%s,kind=host,source=%s", localVolName, ctx.TaskDir.LocalDir)) prepareArgs = append(prepareArgs, fmt.Sprintf("--mount=volume=%s,target=%s", localVolName, allocdir.TaskLocalContainerPath)) // Mount /secrets secretsVolName := fmt.Sprintf("%s-%s-secrets", d.DriverContext.allocID, sanitizedName) prepareArgs = append(prepareArgs, fmt.Sprintf("--volume=%s,kind=host,source=%s", secretsVolName, ctx.TaskDir.SecretsDir)) prepareArgs = append(prepareArgs, fmt.Sprintf("--mount=volume=%s,target=%s", secretsVolName, allocdir.TaskSecretsContainerPath)) // Mount arbitrary volumes if enabled if len(driverConfig.Volumes) > 0 { if enabled := d.config.ReadBoolDefault(rktVolumesConfigOption, rktVolumesConfigDefault); !enabled { return nil, fmt.Errorf("%s is false; cannot use rkt volumes: %+q", rktVolumesConfigOption, driverConfig.Volumes) } for i, rawvol := range driverConfig.Volumes { parts := strings.Split(rawvol, ":") readOnly := "false" // job spec: // volumes = ["/host/path:/container/path[:readOnly]"] // the third parameter is optional, mount is read-write by default if len(parts) == 3 { if parts[2] == "readOnly" { d.logger.Printf("[DEBUG] Mounting %s:%s as readOnly", parts[0], parts[1]) readOnly = "true" } else { d.logger.Printf("[WARN] Unknown volume parameter '%s' ignored for mount %s", parts[2], parts[0]) } } else if len(parts) != 2 { return nil, fmt.Errorf("invalid rkt volume: %q", rawvol) } volName := fmt.Sprintf("%s-%s-%d", d.DriverContext.allocID, sanitizedName, i) prepareArgs = append(prepareArgs, fmt.Sprintf("--volume=%s,kind=host,source=%s,readOnly=%s", volName, parts[0], readOnly)) prepareArgs = append(prepareArgs, fmt.Sprintf("--mount=volume=%s,target=%s", volName, parts[1])) } } // Inject environment variables for k, v := range ctx.TaskEnv.Map() { prepareArgs = append(prepareArgs, fmt.Sprintf("--set-env=%s=%s", k, v)) } // Image is set here, because the commands that follow apply to it prepareArgs = append(prepareArgs, img) // Check if the user has overridden the exec command. if driverConfig.Command != "" { prepareArgs = append(prepareArgs, fmt.Sprintf("--exec=%v", driverConfig.Command)) } // Add memory isolator prepareArgs = append(prepareArgs, fmt.Sprintf("--memory=%vM", int64(task.Resources.MemoryMB))) // Add CPU isolator prepareArgs = append(prepareArgs, fmt.Sprintf("--cpu=%vm", int64(task.Resources.CPU))) // Add DNS servers if len(driverConfig.DNSServers) == 1 && (driverConfig.DNSServers[0] == "host" || driverConfig.DNSServers[0] == "none") { // Special case single item lists with the special values "host" or "none" runArgs = append(runArgs, fmt.Sprintf("--dns=%s", driverConfig.DNSServers[0])) } else { for _, ip := range driverConfig.DNSServers { if err := net.ParseIP(ip); err == nil { msg := fmt.Errorf("invalid ip address for container dns server %q", ip) d.logger.Printf("[DEBUG] driver.rkt: %v", msg) return nil, msg } else { runArgs = append(runArgs, fmt.Sprintf("--dns=%s", ip)) } } } // set DNS search domains for _, domain := range driverConfig.DNSSearchDomains { runArgs = append(runArgs, fmt.Sprintf("--dns-search=%s", domain)) } // set network network := strings.Join(driverConfig.Net, ",") if network != "" { runArgs = append(runArgs, fmt.Sprintf("--net=%s", network)) } // Setup port mapping and exposed ports if len(task.Resources.Networks) == 0 { d.logger.Println("[DEBUG] driver.rkt: No network interfaces are available") if len(driverConfig.PortMap) > 0 { return nil, fmt.Errorf("Trying to map ports but no network interface is available") } } else { // TODO add support for more than one network network := task.Resources.Networks[0] for _, port := range network.ReservedPorts { var containerPort string mapped, ok := driverConfig.PortMap[port.Label] if !ok { // If the user doesn't have a mapped port using port_map, driver stops running container. return nil, fmt.Errorf("port_map is not set. When you defined port in the resources, you need to configure port_map.") } containerPort = mapped hostPortStr := strconv.Itoa(port.Value) d.logger.Printf("[DEBUG] driver.rkt: exposed port %s", containerPort) // Add port option to rkt run arguments. rkt allows multiple port args prepareArgs = append(prepareArgs, fmt.Sprintf("--port=%s:%s", containerPort, hostPortStr)) } for _, port := range network.DynamicPorts { // By default we will map the allocated port 1:1 to the container var containerPort string if mapped, ok := driverConfig.PortMap[port.Label]; ok { containerPort = mapped } else { // If the user doesn't have mapped a port using port_map, driver stops running container. return nil, fmt.Errorf("port_map is not set. When you defined port in the resources, you need to configure port_map.") } hostPortStr := strconv.Itoa(port.Value) d.logger.Printf("[DEBUG] driver.rkt: exposed port %s", containerPort) // Add port option to rkt run arguments. rkt allows multiple port args prepareArgs = append(prepareArgs, fmt.Sprintf("--port=%s:%s", containerPort, hostPortStr)) } } // Add user passed arguments. if len(driverConfig.Args) != 0 { parsed := ctx.TaskEnv.ParseAndReplace(driverConfig.Args) // Need to start arguments with "--" if len(parsed) > 0 { prepareArgs = append(prepareArgs, "--") } for _, arg := range parsed { prepareArgs = append(prepareArgs, fmt.Sprintf("%v", arg)) } } pluginLogFile := filepath.Join(ctx.TaskDir.Dir, fmt.Sprintf("%s-executor.out", task.Name)) executorConfig := &dstructs.ExecutorConfig{ LogFile: pluginLogFile, LogLevel: d.config.LogLevel, } execIntf, pluginClient, err := createExecutor(d.config.LogOutput, d.config, executorConfig) if err != nil { return nil, err } absPath, err := GetAbsolutePath(rktCmd) if err != nil { return nil, err } var outBuf, errBuf bytes.Buffer cmd := exec.Command(rktCmd, prepareArgs...) cmd.Stdout = &outBuf cmd.Stderr = &errBuf d.logger.Printf("[DEBUG] driver.rkt: preparing pod %q for task %q with: %v", img, d.taskName, prepareArgs) if err := cmd.Run(); err != nil { return nil, fmt.Errorf("Error preparing rkt pod: %s\n\nOutput: %s\n\nError: %s", err, outBuf.String(), errBuf.String()) } uuid := strings.TrimSpace(outBuf.String()) d.logger.Printf("[DEBUG] driver.rkt: pod %q for task %q prepared, UUID is: %s", img, d.taskName, uuid) runArgs = append(runArgs, uuid) // The task's environment is set via --set-env flags above, but the rkt // command itself needs an evironment with PATH set to find iptables. eb := env.NewEmptyBuilder() filter := strings.Split(d.config.ReadDefault("env.blacklist", config.DefaultEnvBlacklist), ",") rktEnv := eb.SetHostEnvvars(filter).Build() executorCtx := &executor.ExecutorContext{ TaskEnv: rktEnv, Driver: "rkt", AllocID: d.DriverContext.allocID, Task: task, TaskDir: ctx.TaskDir.Dir, LogDir: ctx.TaskDir.LogDir, } if err := execIntf.SetContext(executorCtx); err != nil { pluginClient.Kill() return nil, fmt.Errorf("failed to set executor context: %v", err) } execCmd := &executor.ExecCommand{ Cmd: absPath, Args: runArgs, User: task.User, } ps, err := execIntf.LaunchCmd(execCmd) if err != nil { pluginClient.Kill() return nil, err } d.logger.Printf("[DEBUG] driver.rkt: started ACI %q (UUID: %s) for task %q with: %v", img, uuid, d.taskName, runArgs) maxKill := d.DriverContext.config.MaxKillTimeout h := &rktHandle{ uuid: uuid, env: rktEnv, taskDir: ctx.TaskDir, pluginClient: pluginClient, executor: execIntf, executorPid: ps.Pid, logger: d.logger, killTimeout: GetKillTimeout(task.KillTimeout, maxKill), maxKillTimeout: maxKill, doneCh: make(chan struct{}), waitCh: make(chan *dstructs.WaitResult, 1), } go h.run() //TODO Set Network return &StartResponse{Handle: h}, nil } func (d *RktDriver) Cleanup(*ExecContext, *CreatedResources) error { return nil } func (d *RktDriver) Open(ctx *ExecContext, handleID string) (DriverHandle, error) { // Parse the handle pidBytes := []byte(strings.TrimPrefix(handleID, "Rkt:")) id := &rktPID{} if err := json.Unmarshal(pidBytes, id); err != nil { return nil, fmt.Errorf("failed to parse Rkt handle '%s': %v", handleID, err) } pluginConfig := &plugin.ClientConfig{ Reattach: id.PluginConfig.PluginConfig(), } exec, pluginClient, err := createExecutorWithConfig(pluginConfig, d.config.LogOutput) if err != nil { d.logger.Println("[ERROR] driver.rkt: error connecting to plugin so destroying plugin pid and user pid") if e := destroyPlugin(id.PluginConfig.Pid, id.ExecutorPid); e != nil { d.logger.Printf("[ERROR] driver.rkt: error destroying plugin and executor pid: %v", e) } return nil, fmt.Errorf("error connecting to plugin: %v", err) } // The task's environment is set via --set-env flags in Start, but the rkt // command itself needs an evironment with PATH set to find iptables. eb := env.NewEmptyBuilder() filter := strings.Split(d.config.ReadDefault("env.blacklist", config.DefaultEnvBlacklist), ",") rktEnv := eb.SetHostEnvvars(filter).Build() ver, _ := exec.Version() d.logger.Printf("[DEBUG] driver.rkt: version of executor: %v", ver.Version) // Return a driver handle h := &rktHandle{ uuid: id.UUID, env: rktEnv, taskDir: ctx.TaskDir, pluginClient: pluginClient, executorPid: id.ExecutorPid, executor: exec, logger: d.logger, killTimeout: id.KillTimeout, maxKillTimeout: id.MaxKillTimeout, doneCh: make(chan struct{}), waitCh: make(chan *dstructs.WaitResult, 1), } go h.run() return h, nil } func (h *rktHandle) ID() string { // Return a handle to the PID pid := &rktPID{ UUID: h.uuid, PluginConfig: NewPluginReattachConfig(h.pluginClient.ReattachConfig()), KillTimeout: h.killTimeout, MaxKillTimeout: h.maxKillTimeout, ExecutorPid: h.executorPid, } data, err := json.Marshal(pid) if err != nil { h.logger.Printf("[ERR] driver.rkt: failed to marshal rkt PID to JSON: %s", err) } return fmt.Sprintf("Rkt:%s", string(data)) } func (h *rktHandle) WaitCh() chan *dstructs.WaitResult { return h.waitCh } func (h *rktHandle) Update(task *structs.Task) error { // Store the updated kill timeout. h.killTimeout = GetKillTimeout(task.KillTimeout, h.maxKillTimeout) h.executor.UpdateTask(task) // Update is not possible return nil } func (h *rktHandle) Exec(ctx context.Context, cmd string, args []string) ([]byte, int, error) { if h.uuid == "" { return nil, 0, fmt.Errorf("unable to find rkt pod UUID") } // enter + UUID + cmd + args... enterArgs := make([]string, 3+len(args)) enterArgs[0] = "enter" enterArgs[1] = h.uuid enterArgs[2] = cmd copy(enterArgs[3:], args) return executor.ExecScript(ctx, h.taskDir.Dir, h.env, nil, rktCmd, enterArgs) } func (h *rktHandle) Signal(s os.Signal) error { return fmt.Errorf("Rkt does not support signals") } // Kill is used to terminate the task. We send an Interrupt // and then provide a 5 second grace period before doing a Kill. func (h *rktHandle) Kill() error { h.executor.ShutDown() select { case <-h.doneCh: return nil case <-time.After(h.killTimeout): return h.executor.Exit() } } func (h *rktHandle) Stats() (*cstructs.TaskResourceUsage, error) { return nil, DriverStatsNotImplemented } func (h *rktHandle) run() { ps, werr := h.executor.Wait() close(h.doneCh) if ps.ExitCode == 0 && werr != nil { if e := killProcess(h.executorPid); e != nil { h.logger.Printf("[ERROR] driver.rkt: error killing user process: %v", e) } } // Exit the executor if err := h.executor.Exit(); err != nil { h.logger.Printf("[ERR] driver.rkt: error killing executor: %v", err) } h.pluginClient.Kill() // Send the results h.waitCh <- dstructs.NewWaitResult(ps.ExitCode, 0, werr) close(h.waitCh) }