Golang execdriver.TweakCapabilities函数代码示例

func finalizeNamespace(args *InitArgs) error {
	if err := utils.CloseExecFrom(3); err != nil {
		return err
	}

	// We use the native drivers default template so that things like caps are consistent
	// across both drivers
	container := template.New()

	if !args.Privileged {
		// drop capabilities in bounding set before changing user
		if err := capabilities.DropBoundingSet(container.Capabilities); err != nil {
			return fmt.Errorf("drop bounding set %s", err)
		}

		// preserve existing capabilities while we change users
		if err := system.SetKeepCaps(); err != nil {
			return fmt.Errorf("set keep caps %s", err)
		}
	}

	if err := namespaces.SetupUser(args.User); err != nil {
		return fmt.Errorf("setup user %s", err)
	}

	if !args.Privileged {
		if err := system.ClearKeepCaps(); err != nil {
			return fmt.Errorf("clear keep caps %s", err)
		}

		var (
			adds  []string
			drops []string
		)

		if args.CapAdd != "" {
			adds = strings.Split(args.CapAdd, ":")
		}
		if args.CapDrop != "" {
			drops = strings.Split(args.CapDrop, ":")
		}

		caps, err := execdriver.TweakCapabilities(container.Capabilities, adds, drops)
		if err != nil {
			return err
		}

		// drop all other capabilities
		if err := capabilities.DropCapabilities(caps); err != nil {
			return fmt.Errorf("drop capabilities %s", err)
		}
	}

	if err := setupWorkingDirectory(args); err != nil {
		return err
	}

	return nil
}

func keepCapabilities(adds []string, drops []string) []string {
	container := nativeTemplate.New()
	caps, err := execdriver.TweakCapabilities(container.Capabilities, adds, drops)
	var newCaps []string
	for _, cap := range caps {
		newCaps = append(newCaps, strings.ToLower(cap))
	}
	if err != nil {
		return []string{}
	}
	return newCaps
}

func keepCapabilities(adds []string, drops []string) ([]string, error) {
	container := nativeTemplate.New()
	logrus.Debugf("adds %s drops %s\n", adds, drops)
	caps, err := execdriver.TweakCapabilities(container.Capabilities, adds, drops)
	if err != nil {
		return nil, err
	}
	var newCaps []string
	for _, cap := range caps {
		logrus.Debugf("cap %s\n", cap)
		realCap := execdriver.GetCapability(cap)
		numCap := fmt.Sprintf("%d", realCap.Value)
		newCaps = append(newCaps, numCap)
	}

	return newCaps, nil
}

func (d *Driver) setCapabilities(container *configs.Config, c *execdriver.Command) (err error) {
	container.Capabilities, err = execdriver.TweakCapabilities(container.Capabilities, c.CapAdd, c.CapDrop)
	return err
}

// Config takes ContainerJSON and Daemon Info and converts it into the opencontainers spec.
func Config(c types.ContainerJSON, info types.Info, capabilities []string) (config *specs.LinuxSpec, err error) {
	config = &specs.LinuxSpec{
		Spec: specs.Spec{
			Version: SpecVersion,
			Platform: specs.Platform{
				OS:   info.OSType,
				Arch: info.Architecture,
			},
			Process: specs.Process{
				Terminal: c.Config.Tty,
				User:     specs.User{
				// TODO: user stuffs
				},
				Args: append([]string{c.Path}, c.Args...),
				Env:  c.Config.Env,
				Cwd:  c.Config.WorkingDir,
			},
			Root: specs.Root{
				Path:     "rootfs",
				Readonly: c.HostConfig.ReadonlyRootfs,
			},
			Mounts: []specs.MountPoint{},
		},
	}

	// make sure the current working directory is not blank
	if config.Process.Cwd == "" {
		config.Process.Cwd = DefaultCurrentWorkingDirectory
	}

	// get the user
	if c.Config.User != "" {
		u, err := user.LookupUser(c.Config.User)
		if err != nil {
			config.Spec.Process.User = specs.User{
				UID: uint32(u.Uid),
				GID: uint32(u.Gid),
			}
		} else {
			//return nil, fmt.Errorf("Looking up user (%s) failed: %v", c.Config.User, err)
			logrus.Warnf("Looking up user (%s) failed: %v", c.Config.User, err)
		}
	}
	// add the additional groups
	for _, group := range c.HostConfig.GroupAdd {
		g, err := user.LookupGroup(group)
		if err != nil {
			return nil, fmt.Errorf("Looking up group (%s) failed: %v", group, err)
		}
		config.Spec.Process.User.AdditionalGids = append(config.Spec.Process.User.AdditionalGids, uint32(g.Gid))
	}

	// get the hostname, if the hostname is the name as the first 12 characters of the id,
	// then set the hostname as the container name
	if c.ID[:12] == c.Config.Hostname {
		config.Hostname = strings.TrimPrefix(c.Name, "/")
	}

	// get mounts
	mounts := map[string]bool{}
	for _, mount := range c.Mounts {
		mounts[mount.Destination] = true
		config.Mounts = append(config.Mounts, specs.MountPoint{
			Name: mount.Destination,
			Path: mount.Destination,
		})
	}

	// add /etc/hosts and /etc/resolv.conf if we should have networking
	if c.HostConfig.NetworkMode != "none" && c.HostConfig.NetworkMode != "host" {
		DefaultMounts = append(DefaultMounts, NetworkMounts...)
	}

	// if we aren't doing something crazy like mounting a default mount ourselves,
	// the we can mount it the default way
	for _, mount := range DefaultMounts {
		if _, ok := mounts[mount.Path]; !ok {
			config.Mounts = append(config.Mounts, mount)
		}
	}

	// set privileged
	if c.HostConfig.Privileged {
		// allow all caps
		capabilities = execdriver.GetAllCapabilities()
	}

	// get the capabilities
	config.Linux.Capabilities, err = execdriver.TweakCapabilities(capabilities, c.HostConfig.CapAdd.Slice(), c.HostConfig.CapDrop.Slice())
	if err != nil {
		return nil, fmt.Errorf("setting capabilities failed: %v", err)
	}

	// add CAP_ prefix
	// TODO: this is awful
	for i, cap := range config.Linux.Capabilities {
		if !strings.HasPrefix(cap, "CAP_") {
			config.Linux.Capabilities[i] = fmt.Sprintf("CAP_%s", cap)
		}
//.........这里部分代码省略.........

//.........这里部分代码省略.........
		u, err := user.LookupUser(c.Config.User)
		if err != nil {
			config.Process.User = specs.User{
				UID: uint32(u.Uid),
				GID: uint32(u.Gid),
			}
		} else {
			//return nil, fmt.Errorf("Looking up user (%s) failed: %v", c.Config.User, err)
			logrus.Warnf("Looking up user (%s) failed: %v", c.Config.User, err)
		}
	}
	// add the additional groups
	for _, group := range c.HostConfig.GroupAdd {
		g, err := user.LookupGroup(group)
		if err != nil {
			return nil, fmt.Errorf("Looking up group (%s) failed: %v", group, err)
		}
		config.Process.User.AdditionalGids = append(config.Process.User.AdditionalGids, uint32(g.Gid))
	}

	// get the hostname, if the hostname is the name as the first 12 characters of the id,
	// then set the hostname as the container name
	if c.ID[:12] == c.Config.Hostname {
		config.Hostname = strings.TrimPrefix(c.Name, "/")
	}

	// set privileged
	if c.HostConfig.Privileged {
		// allow all caps
		capabilities = execdriver.GetAllCapabilities()
	}

	// get the capabilities
	config.Process.Capabilities, err = execdriver.TweakCapabilities(capabilities, c.HostConfig.CapAdd, c.HostConfig.CapDrop)
	if err != nil {
		return nil, fmt.Errorf("setting capabilities failed: %v", err)
	}

	// add CAP_ prefix
	// TODO: this is awful
	for i, cap := range config.Process.Capabilities {
		if !strings.HasPrefix(cap, "CAP_") {
			config.Process.Capabilities[i] = fmt.Sprintf("CAP_%s", cap)
		}
	}

	// if we have a container that needs a terminal but no env vars, then set
	// default env vars for the terminal to function
	if config.Process.Terminal && len(config.Process.Env) <= 0 {
		config.Process.Env = DefaultTerminalEnv
	}
	if config.Process.Terminal {
		// make sure we have TERM set
		var termSet bool
		for _, env := range config.Process.Env {
			if strings.HasPrefix(env, "TERM=") {
				termSet = true
				break
			}
		}
		if !termSet {
			// set the term variable
			config.Process.Env = append(config.Process.Env, fmt.Sprintf("TERM=%s", DefaultTerminal))
		}
	}