| package execdriver |
| |
| import ( |
| "encoding/json" |
| "errors" |
| "io" |
| "io/ioutil" |
| "os" |
| "os/exec" |
| "path/filepath" |
| "strconv" |
| "strings" |
| "time" |
| |
| "github.com/docker/docker/daemon/execdriver/native/template" |
| "github.com/docker/docker/pkg/ulimit" |
| "github.com/docker/libcontainer" |
| "github.com/docker/libcontainer/cgroups/fs" |
| "github.com/docker/libcontainer/configs" |
| ) |
| |
| // Context is a generic key value pair that allows |
| // arbatrary data to be sent |
| type Context map[string]string |
| |
| var ( |
| ErrNotRunning = errors.New("Container is not running") |
| ErrWaitTimeoutReached = errors.New("Wait timeout reached") |
| ErrDriverAlreadyRegistered = errors.New("A driver already registered this docker init function") |
| ErrDriverNotFound = errors.New("The requested docker init has not been found") |
| ) |
| |
| type StartCallback func(*ProcessConfig, int) |
| |
| // Driver specific information based on |
| // processes registered with the driver |
| type Info interface { |
| IsRunning() bool |
| } |
| |
| // Terminal in an interface for drivers to implement |
| // if they want to support Close and Resize calls from |
| // the core |
| type Terminal interface { |
| io.Closer |
| Resize(height, width int) error |
| } |
| |
| type TtyTerminal interface { |
| Master() libcontainer.Console |
| } |
| |
| // ExitStatus provides exit reasons for a container. |
| type ExitStatus struct { |
| // The exit code with which the container exited. |
| ExitCode int |
| |
| // Whether the container encountered an OOM. |
| OOMKilled bool |
| } |
| |
| type Driver interface { |
| Run(c *Command, pipes *Pipes, startCallback StartCallback) (ExitStatus, error) // Run executes the process and blocks until the process exits and returns the exit code |
| // Exec executes the process in an existing container, blocks until the process exits and returns the exit code |
| Exec(c *Command, processConfig *ProcessConfig, pipes *Pipes, startCallback StartCallback) (int, error) |
| Kill(c *Command, sig int) error |
| Pause(c *Command) error |
| Unpause(c *Command) error |
| Name() string // Driver name |
| Info(id string) Info // "temporary" hack (until we move state from core to plugins) |
| GetPidsForContainer(id string) ([]int, error) // Returns a list of pids for the given container. |
| Terminate(c *Command) error // kill it with fire |
| Clean(id string) error // clean all traces of container exec |
| Stats(id string) (*ResourceStats, error) // Get resource stats for a running container |
| } |
| |
| // Network settings of the container |
| type Network struct { |
| Interface *NetworkInterface `json:"interface"` // if interface is nil then networking is disabled |
| Mtu int `json:"mtu"` |
| ContainerID string `json:"container_id"` // id of the container to join network. |
| HostNetworking bool `json:"host_networking"` |
| } |
| |
| // IPC settings of the container |
| type Ipc struct { |
| ContainerID string `json:"container_id"` // id of the container to join ipc. |
| HostIpc bool `json:"host_ipc"` |
| } |
| |
| // PID settings of the container |
| type Pid struct { |
| HostPid bool `json:"host_pid"` |
| } |
| |
| type NetworkInterface struct { |
| Gateway string `json:"gateway"` |
| IPAddress string `json:"ip"` |
| IPPrefixLen int `json:"ip_prefix_len"` |
| MacAddress string `json:"mac"` |
| Bridge string `json:"bridge"` |
| GlobalIPv6Address string `json:"global_ipv6"` |
| LinkLocalIPv6Address string `json:"link_local_ipv6"` |
| GlobalIPv6PrefixLen int `json:"global_ipv6_prefix_len"` |
| IPv6Gateway string `json:"ipv6_gateway"` |
| } |
| |
| type Resources struct { |
| Memory int64 `json:"memory"` |
| MemorySwap int64 `json:"memory_swap"` |
| CpuShares int64 `json:"cpu_shares"` |
| CpusetCpus string `json:"cpuset_cpus"` |
| Rlimits []*ulimit.Rlimit `json:"rlimits"` |
| } |
| |
| type ResourceStats struct { |
| *libcontainer.Stats |
| Read time.Time `json:"read"` |
| MemoryLimit int64 `json:"memory_limit"` |
| SystemUsage uint64 `json:"system_usage"` |
| } |
| |
| type Mount struct { |
| Source string `json:"source"` |
| Destination string `json:"destination"` |
| Writable bool `json:"writable"` |
| Private bool `json:"private"` |
| Slave bool `json:"slave"` |
| } |
| |
| // Describes a process that will be run inside a container. |
| type ProcessConfig struct { |
| exec.Cmd `json:"-"` |
| |
| Privileged bool `json:"privileged"` |
| User string `json:"user"` |
| Tty bool `json:"tty"` |
| Entrypoint string `json:"entrypoint"` |
| Arguments []string `json:"arguments"` |
| Terminal Terminal `json:"-"` // standard or tty terminal |
| Console string `json:"-"` // dev/console path |
| } |
| |
| // Process wrapps an os/exec.Cmd to add more metadata |
| type Command struct { |
| ID string `json:"id"` |
| Rootfs string `json:"rootfs"` // root fs of the container |
| ReadonlyRootfs bool `json:"readonly_rootfs"` |
| InitPath string `json:"initpath"` // dockerinit |
| WorkingDir string `json:"working_dir"` |
| ConfigPath string `json:"config_path"` // this should be able to be removed when the lxc template is moved into the driver |
| Network *Network `json:"network"` |
| Ipc *Ipc `json:"ipc"` |
| Pid *Pid `json:"pid"` |
| Resources *Resources `json:"resources"` |
| Mounts []Mount `json:"mounts"` |
| AllowedDevices []*configs.Device `json:"allowed_devices"` |
| AutoCreatedDevices []*configs.Device `json:"autocreated_devices"` |
| CapAdd []string `json:"cap_add"` |
| CapDrop []string `json:"cap_drop"` |
| ContainerPid int `json:"container_pid"` // the pid for the process inside a container |
| ProcessConfig ProcessConfig `json:"process_config"` // Describes the init process of the container. |
| ProcessLabel string `json:"process_label"` |
| MountLabel string `json:"mount_label"` |
| LxcConfig []string `json:"lxc_config"` |
| AppArmorProfile string `json:"apparmor_profile"` |
| CgroupParent string `json:"cgroup_parent"` // The parent cgroup for this command. |
| } |
| |
| func InitContainer(c *Command) *configs.Config { |
| container := template.New() |
| |
| container.Hostname = getEnv("HOSTNAME", c.ProcessConfig.Env) |
| container.Cgroups.Name = c.ID |
| container.Cgroups.AllowedDevices = c.AllowedDevices |
| container.Readonlyfs = c.ReadonlyRootfs |
| container.Devices = c.AutoCreatedDevices |
| container.Rootfs = c.Rootfs |
| container.Readonlyfs = c.ReadonlyRootfs |
| |
| // check to see if we are running in ramdisk to disable pivot root |
| container.NoPivotRoot = os.Getenv("DOCKER_RAMDISK") != "" |
| |
| // Default parent cgroup is "docker". Override if required. |
| if c.CgroupParent != "" { |
| container.Cgroups.Parent = c.CgroupParent |
| } |
| return container |
| } |
| |
| func getEnv(key string, env []string) string { |
| for _, pair := range env { |
| parts := strings.Split(pair, "=") |
| if parts[0] == key { |
| return parts[1] |
| } |
| } |
| return "" |
| } |
| |
| func SetupCgroups(container *configs.Config, c *Command) error { |
| if c.Resources != nil { |
| container.Cgroups.CpuShares = c.Resources.CpuShares |
| container.Cgroups.Memory = c.Resources.Memory |
| container.Cgroups.MemoryReservation = c.Resources.Memory |
| container.Cgroups.MemorySwap = c.Resources.MemorySwap |
| container.Cgroups.CpusetCpus = c.Resources.CpusetCpus |
| } |
| |
| return nil |
| } |
| |
| // Returns the network statistics for the network interfaces represented by the NetworkRuntimeInfo. |
| func getNetworkInterfaceStats(interfaceName string) (*libcontainer.NetworkInterface, error) { |
| out := &libcontainer.NetworkInterface{Name: interfaceName} |
| // This can happen if the network runtime information is missing - possible if the |
| // container was created by an old version of libcontainer. |
| if interfaceName == "" { |
| return out, nil |
| } |
| type netStatsPair struct { |
| // Where to write the output. |
| Out *uint64 |
| // The network stats file to read. |
| File string |
| } |
| // Ingress for host veth is from the container. Hence tx_bytes stat on the host veth is actually number of bytes received by the container. |
| netStats := []netStatsPair{ |
| {Out: &out.RxBytes, File: "tx_bytes"}, |
| {Out: &out.RxPackets, File: "tx_packets"}, |
| {Out: &out.RxErrors, File: "tx_errors"}, |
| {Out: &out.RxDropped, File: "tx_dropped"}, |
| |
| {Out: &out.TxBytes, File: "rx_bytes"}, |
| {Out: &out.TxPackets, File: "rx_packets"}, |
| {Out: &out.TxErrors, File: "rx_errors"}, |
| {Out: &out.TxDropped, File: "rx_dropped"}, |
| } |
| for _, netStat := range netStats { |
| data, err := readSysfsNetworkStats(interfaceName, netStat.File) |
| if err != nil { |
| return nil, err |
| } |
| *(netStat.Out) = data |
| } |
| return out, nil |
| } |
| |
| // Reads the specified statistics available under /sys/class/net/<EthInterface>/statistics |
| func readSysfsNetworkStats(ethInterface, statsFile string) (uint64, error) { |
| data, err := ioutil.ReadFile(filepath.Join("/sys/class/net", ethInterface, "statistics", statsFile)) |
| if err != nil { |
| return 0, err |
| } |
| return strconv.ParseUint(strings.TrimSpace(string(data)), 10, 64) |
| } |
| |
| func Stats(containerDir string, containerMemoryLimit int64, machineMemory int64) (*ResourceStats, error) { |
| f, err := os.Open(filepath.Join(containerDir, "state.json")) |
| if err != nil { |
| return nil, err |
| } |
| defer f.Close() |
| |
| type network struct { |
| Type string |
| HostInterfaceName string |
| } |
| |
| state := struct { |
| CgroupPaths map[string]string `json:"cgroup_paths"` |
| Networks []network |
| }{} |
| |
| if err := json.NewDecoder(f).Decode(&state); err != nil { |
| return nil, err |
| } |
| now := time.Now() |
| |
| mgr := fs.Manager{Paths: state.CgroupPaths} |
| cstats, err := mgr.GetStats() |
| if err != nil { |
| return nil, err |
| } |
| stats := &libcontainer.Stats{CgroupStats: cstats} |
| // if the container does not have any memory limit specified set the |
| // limit to the machines memory |
| memoryLimit := containerMemoryLimit |
| if memoryLimit == 0 { |
| memoryLimit = machineMemory |
| } |
| for _, iface := range state.Networks { |
| switch iface.Type { |
| case "veth": |
| istats, err := getNetworkInterfaceStats(iface.HostInterfaceName) |
| if err != nil { |
| return nil, err |
| } |
| stats.Interfaces = append(stats.Interfaces, istats) |
| } |
| } |
| return &ResourceStats{ |
| Stats: stats, |
| Read: now, |
| MemoryLimit: memoryLimit, |
| }, nil |
| } |