Golang syscall.Setgroups函数代码示例

func (UserExecer) ExecAsUser(uid, gid int, workDir, programName string, args ...string) error {
	if _, _, errNo := syscall.RawSyscall(syscall.SYS_SETGID, uintptr(gid), 0, 0); errNo != 0 {
		return fmt.Errorf("system: setgid: %s", errNo.Error())
	}

	if err := syscall.Setgroups([]int{}); err != nil {
		return fmt.Errorf("system: setgroups: %s", err)
	}

	if _, _, errNo := syscall.RawSyscall(syscall.SYS_SETUID, uintptr(uid), 0, 0); errNo != 0 {
		return fmt.Errorf("system: setuid: %s", errNo.Error())
	}

	if workDir == "" {
		return errors.New("system: working directory is not provided.")
	}

	if err := os.MkdirAll(workDir, 0755); err != nil {
		return fmt.Errorf("system: %s", err)
	}

	if err := os.Chdir(workDir); err != nil {
		return fmt.Errorf("system: invalid working directory: %s", workDir)
	}

	programPath, err := exec.LookPath(programName)
	if err != nil {
		return fmt.Errorf("system: program '%s' was not found in $PATH: %s", programName, err)
	}

	if err := syscall.Exec(programPath, append([]string{programName}, args...), os.Environ()); err != nil {
		return fmt.Errorf("system: exec of %s: %s", programName, err)
	}
	return nil
}

// SetupUser changes the groups, gid, and uid for the user inside the container
func SetupUser(u string) error {
	uid, gid, suppGids, home, err := user.GetUserGroupSupplementaryHome(u, syscall.Getuid(), syscall.Getgid(), "/")
	if err != nil {
		return fmt.Errorf("get supplementary groups %s", err)
	}

	if err := syscall.Setgroups(suppGids); err != nil {
		return fmt.Errorf("setgroups %s", err)
	}

	if err := syscall.Setgid(gid); err != nil {
		return fmt.Errorf("setgid %s", err)
	}

	if err := syscall.Setuid(uid); err != nil {
		return fmt.Errorf("setuid %s", err)
	}

	// if we didn't get HOME already, set it based on the user's HOME
	if envHome := os.Getenv("HOME"); envHome == "" {
		if err := os.Setenv("HOME", home); err != nil {
			return fmt.Errorf("set HOME %s", err)
		}
	}

	return nil
}

func DropPrivileges(username string) error {
	userInfo, err := user.Lookup(username)
	if err != nil {
		return err
	}

	uid, err := strconv.Atoi(userInfo.Uid)
	if err != nil {
		return err
	}

	gid, err := strconv.Atoi(userInfo.Gid)
	if err != nil {
		return err
	}

	// TODO: should set secondary groups too
	err = syscall.Setgroups([]int{gid})
	if err != nil {
		return err
	}

	err = syscall.Setgid(gid)
	if err != nil {
		return err
	}

	err = syscall.Setuid(uid)
	if err != nil {
		return err
	}

	return nil
}

// SetupUser changes the groups, gid, and uid for the user inside the container
func SetupUser(u string) error {
	// Set up defaults.
	defaultExecUser := user.ExecUser{
		Uid:  syscall.Getuid(),
		Gid:  syscall.Getgid(),
		Home: "/",
	}
	passwdPath, err := user.GetPasswdPath()
	if err != nil {
		return err
	}
	groupPath, err := user.GetGroupPath()
	if err != nil {
		return err
	}

	execUser, err := user.GetExecUserPath(u, &defaultExecUser, passwdPath, groupPath)
	if err != nil {
		return fmt.Errorf("get supplementary groups %s", err)
	}

	// if not root - check uid/gid by hand if seccomp is not working
	if syscall.Geteuid() > 0 && (execUser.Uid <= MIN_UID || execUser.Gid <= MIN_GID) {
		return fmt.Errorf("Invalid UID or GID")
	}

	// set supplementary groups
	if err := syscall.Setgroups(execUser.Sgids); err != nil {
		return fmt.Errorf("setgroups %s", err)
	}

	// set gid
	if err := system.Setgid(execUser.Gid); err != nil {
		return fmt.Errorf("setgid %s", err)
	}

	// check if setgid is successfull
	if syscall.Getgid() != execUser.Gid {
		return fmt.Errorf("setgid failed")
	}

	// set uid
	if err := system.Setuid(execUser.Uid); err != nil {
		return fmt.Errorf("setuid %s", err)
	}

	// check if setuid is successful
	if syscall.Getuid() != execUser.Uid {
		return fmt.Errorf("setuid failed")
	}

	// if we didn't get HOME already, set it based on the user's HOME
	if envHome := os.Getenv("HOME"); envHome == "" {
		if err := os.Setenv("HOME", execUser.Home); err != nil {
			return fmt.Errorf("set HOME %s", err)
		}
	}
	return nil
}

// setupUser changes the groups, gid, and uid for the user inside the container
func setupUser(config *initConfig) error {
	// Set up defaults.
	defaultExecUser := user.ExecUser{
		Uid:  syscall.Getuid(),
		Gid:  syscall.Getgid(),
		Home: "/",
	}
	passwdPath, err := user.GetPasswdPath()
	if err != nil {
		return err
	}
	groupPath, err := user.GetGroupPath()
	if err != nil {
		return err
	}
	execUser, err := user.GetExecUserPath(config.User, &defaultExecUser, passwdPath, groupPath)
	if err != nil {
		return err
	}

	var addGroups []int
	if len(config.Config.AdditionalGroups) > 0 {
		addGroups, err = user.GetAdditionalGroupsPath(config.Config.AdditionalGroups, groupPath)
		if err != nil {
			return err
		}
	}
	// change the permissions on the STDIO of the current process so that when the user
	// is changed for the container, it's STDIO of the process matches the user.
	for _, fd := range []uintptr{
		os.Stdin.Fd(),
		os.Stderr.Fd(),
		os.Stdout.Fd(),
	} {
		if err := syscall.Fchown(int(fd), execUser.Uid, execUser.Gid); err != nil {
			return err
		}
	}
	suppGroups := append(execUser.Sgids, addGroups...)
	if err := syscall.Setgroups(suppGroups); err != nil {
		return err
	}

	if err := system.Setgid(execUser.Gid); err != nil {
		return err
	}
	if err := system.Setuid(execUser.Uid); err != nil {
		return err
	}
	// if we didn't get HOME already, set it based on the user's HOME
	if envHome := os.Getenv("HOME"); envHome == "" {
		if err := os.Setenv("HOME", execUser.Home); err != nil {
			return err
		}
	}
	return nil
}

// setupUser changes the groups, gid, and uid for the user inside the container
func setupUser(config *initConfig) error {
	// Set up defaults.
	defaultExecUser := user.ExecUser{
		Uid:  syscall.Getuid(),
		Gid:  syscall.Getgid(),
		Home: "/",
	}
	passwdPath, err := user.GetPasswdPath()
	if err != nil {
		return err
	}
	groupPath, err := user.GetGroupPath()
	if err != nil {
		return err
	}
	execUser, err := user.GetExecUserPath(config.User, &defaultExecUser, passwdPath, groupPath)
	if err != nil {
		return err
	}

	var addGroups []int
	if len(config.Config.AdditionalGroups) > 0 {
		addGroups, err = user.GetAdditionalGroupsPath(config.Config.AdditionalGroups, groupPath)
		if err != nil {
			return err
		}
	}
	// before we change to the container's user make sure that the processes STDIO
	// is correctly owned by the user that we are switching to.
	if err := fixStdioPermissions(execUser); err != nil {
		return err
	}
	suppGroups := append(execUser.Sgids, addGroups...)
	if err := syscall.Setgroups(suppGroups); err != nil {
		return err
	}

	if err := system.Setgid(execUser.Gid); err != nil {
		return err
	}
	if err := system.Setuid(execUser.Uid); err != nil {
		return err
	}
	// if we didn't get HOME already, set it based on the user's HOME
	if envHome := os.Getenv("HOME"); envHome == "" {
		if err := os.Setenv("HOME", execUser.Home); err != nil {
			return err
		}
	}
	return nil
}

func MaybeBecomeChildProcess() {
	lrs := os.Getenv("_RUNSIT_LAUNCH_INFO")
	if lrs == "" {
		return
	}
	defer os.Exit(2) // should never make it this far, though

	lr := new(LaunchRequest)
	d := gob.NewDecoder(base64.NewDecoder(base64.StdEncoding, strings.NewReader(lrs)))
	err := d.Decode(lr)
	if err != nil {
		log.Fatalf("Failed to decode LaunchRequest in child: %v", err)
	}
	if lr.NumFiles != 0 {
		var lim syscall.Rlimit
		if err := syscall.Getrlimit(syscall.RLIMIT_NOFILE, &lim); err != nil {
			log.Fatalf("failed to get NOFILE rlimit: %v", err)
		}
		noFile := rlim_t(lr.NumFiles)
		lim.Cur = noFile
		lim.Max = noFile
		if err := syscall.Setrlimit(syscall.RLIMIT_NOFILE, &lim); err != nil {
			log.Fatalf("failed to set NOFILE rlimit: %v", err)
		}
	}
	if lr.Gid != 0 {
		if err := syscall.Setgid(lr.Gid); err != nil {
			log.Fatalf("failed to Setgid(%d): %v", lr.Gid, err)
		}
	}
	if len(lr.Gids) != 0 {
		if err := syscall.Setgroups(lr.Gids); err != nil {
			log.Printf("setgroups: %v", err)
		}
	}
	if lr.Uid != 0 {
		if err := syscall.Setuid(lr.Uid); err != nil {
			log.Fatalf("failed to Setuid(%d): %v", lr.Uid, err)
		}
	}
	if lr.Path != "" {
		err = os.Chdir(lr.Dir)
		if err != nil {
			log.Fatalf("failed to chdir to %q: %v", lr.Dir, err)
		}
	}
	err = syscall.Exec(lr.Path, lr.Argv, lr.Env)
	log.Fatalf("failed to exec %q: %v", lr.Path, err)
}

// setupUser changes the groups, gid, and uid for the user inside the container
func setupUser(config *initConfig) error {
	// Set up defaults.
	defaultExecUser := user.ExecUser{
		Uid:  syscall.Getuid(),
		Gid:  syscall.Getgid(),
		Home: "/",
	}
	passwdPath, err := user.GetPasswdPath()
	if err != nil {
		return err
	}
	groupPath, err := user.GetGroupPath()
	if err != nil {
		return err
	}
	execUser, err := user.GetExecUserPath(config.User, &defaultExecUser, passwdPath, groupPath)
	if err != nil {
		return err
	}

	var addGroups []int
	if len(config.Config.AdditionalGroups) > 0 {
		addGroups, err = user.GetAdditionalGroupsPath(config.Config.AdditionalGroups, groupPath)
		if err != nil {
			return err
		}
	}

	suppGroups := append(execUser.Sgids, addGroups...)
	if err := syscall.Setgroups(suppGroups); err != nil {
		return err
	}

	if err := system.Setgid(execUser.Gid); err != nil {
		return err
	}
	if err := system.Setuid(execUser.Uid); err != nil {
		return err
	}
	// if we didn't get HOME already, set it based on the user's HOME
	if envHome := os.Getenv("HOME"); envHome == "" {
		if err := os.Setenv("HOME", execUser.Home); err != nil {
			return err
		}
	}
	return nil
}

// SetupUser changes the groups, gid, and uid for the user inside the container
func SetupUser(container *libcontainer.Config) error {
	// Set up defaults.
	defaultExecUser := user.ExecUser{
		Uid:  syscall.Getuid(),
		Gid:  syscall.Getgid(),
		Home: "/",
	}

	passwdPath, err := user.GetPasswdPath()
	if err != nil {
		return err
	}

	groupPath, err := user.GetGroupPath()
	if err != nil {
		return err
	}

	execUser, err := user.GetExecUserPath(container.User, &defaultExecUser, passwdPath, groupPath)
	if err != nil {
		return fmt.Errorf("get supplementary groups %s", err)
	}

	suppGroups := append(execUser.Sgids, container.AdditionalGroups...)

	if err := syscall.Setgroups(suppGroups); err != nil {
		return fmt.Errorf("setgroups %s", err)
	}

	if err := system.Setgid(execUser.Gid); err != nil {
		return fmt.Errorf("setgid %s", err)
	}

	if err := system.Setuid(execUser.Uid); err != nil {
		return fmt.Errorf("setuid %s", err)
	}

	// if we didn't get HOME already, set it based on the user's HOME
	if envHome := os.Getenv("HOME"); envHome == "" {
		if err := os.Setenv("HOME", execUser.Home); err != nil {
			return fmt.Errorf("set HOME %s", err)
		}
	}

	return nil
}

func changeUser(name string) error {
	user, err := user.Lookup(name)
	if err != nil {
		return err
	}
	uid, err := strconv.Atoi(user.Uid)
	if err != nil {
		return err
	}
	gid, err := strconv.Atoi(user.Gid)
	if err = syscall.Setgroups([]int{gid}); err != nil {
		return err
	}
	if err = syscall.Setuid(uid); err != nil {
		return err
	}
	return nil
}

// SetupUser changes the groups, gid, and uid for the user inside the container
func SetupUser(u string) error {
	// Set up defaults.
	defaultExecUser := user.ExecUser{
		Uid:  syscall.Getuid(),
		Gid:  syscall.Getgid(),
		Home: "/",
	}

	passwdFile, err := user.GetPasswdFile()
	if err != nil {
		return err
	}

	groupFile, err := user.GetGroupFile()
	if err != nil {
		return err
	}

	execUser, err := user.GetExecUserFile(u, &defaultExecUser, passwdFile, groupFile)
	if err != nil {
		return fmt.Errorf("get supplementary groups %s", err)
	}

	if err := syscall.Setgroups(execUser.Sgids); err != nil {
		return fmt.Errorf("setgroups %s", err)
	}

	if err := system.Setgid(execUser.Gid); err != nil {
		return fmt.Errorf("setgid %s", err)
	}

	if err := system.Setuid(execUser.Uid); err != nil {
		return fmt.Errorf("setuid %s", err)
	}

	// if we didn't get HOME already, set it based on the user's HOME
	if envHome := os.Getenv("HOME"); envHome == "" {
		if err := os.Setenv("HOME", execUser.Home); err != nil {
			return fmt.Errorf("set HOME %s", err)
		}
	}

	return nil
}

// SetupUser changes the groups, gid, and uid for the user inside the container
func SetupUser(u string) error {
	uid, gid, suppGids, err := user.GetUserGroupSupplementary(u, syscall.Getuid(), syscall.Getgid())
	if err != nil {
		return fmt.Errorf("get supplementary groups %s", err)
	}

	if err := syscall.Setgroups(suppGids); err != nil {
		return fmt.Errorf("setgroups %s", err)
	}

	if err := syscall.Setgid(gid); err != nil {
		return fmt.Errorf("setgid %s", err)
	}

	if err := syscall.Setuid(uid); err != nil {
		return fmt.Errorf("setuid %s", err)
	}

	return nil
}

// Takes care of dropping privileges to the desired user
func changeUser(args *execdriver.InitArgs) error {
	uid, gid, suppGids, err := user.GetUserGroupSupplementary(
		args.User,
		syscall.Getuid(), syscall.Getgid(),
	)
	if err != nil {
		return err
	}

	if err := syscall.Setgroups(suppGids); err != nil {
		return fmt.Errorf("Setgroups failed: %v", err)
	}
	if err := syscall.Setgid(gid); err != nil {
		return fmt.Errorf("Setgid failed: %v", err)
	}
	if err := syscall.Setuid(uid); err != nil {
		return fmt.Errorf("Setuid failed: %v", err)
	}

	return nil
}

// setupUser changes the groups, gid, and uid for the user inside the container
// copy from libcontainer, cause not it's private
func setupUser(userSpec string) error {
	// Set up defaults.
	defaultExecUser := user.ExecUser{
		Uid:  syscall.Getuid(),
		Gid:  syscall.Getgid(),
		Home: "/",
	}
	passwdPath, err := user.GetPasswdPath()
	if err != nil {
		return err
	}
	groupPath, err := user.GetGroupPath()
	if err != nil {
		return err
	}
	execUser, err := user.GetExecUserPath(userSpec, &defaultExecUser, passwdPath, groupPath)
	if err != nil {
		return err
	}
	if err := syscall.Setgroups(execUser.Sgids); err != nil {
		return err
	}
	if err := system.Setgid(execUser.Gid); err != nil {
		return err
	}
	if err := system.Setuid(execUser.Uid); err != nil {
		return err
	}
	// if we didn't get HOME already, set it based on the user's HOME
	if envHome := os.Getenv("HOME"); envHome == "" {
		if err := os.Setenv("HOME", execUser.Home); err != nil {
			return err
		}
	}
	return nil
}

// SetupUser changes the groups, gid, and uid for the user inside the container
func SetupUser(u string) error {
	// Set up defaults.
	defaultExecUser := user.ExecUser{
		Uid:  syscall.Getuid(),
		Gid:  syscall.Getgid(),
		Home: "/",
	}

	execUser, err := getUser(u, &defaultExecUser)
	if err != nil {
		return err
	}

	if err := syscall.Setgroups(execUser.Sgids); err != nil {
		return fmt.Errorf("setgroups %s", err)
	}

	if err := system.Setgid(execUser.Gid); err != nil {
		return fmt.Errorf("setgid %s", err)
	}

	if err := system.Setuid(execUser.Uid); err != nil {
		return fmt.Errorf("setuid %s", err)
	}

	// if we didn't get HOME already, set it based on the user's HOME
	if envHome := os.Getenv("HOME"); envHome == "" {
		if err := os.Setenv("HOME", execUser.Home); err != nil {
			return fmt.Errorf("set HOME %s", err)
		}
	}

	os.Setenv("USER", u)

	return nil
}