mirror of
https://github.com/tailscale/tailscale.git
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ssh/tailssh: fall back to using su when no TTY available on Linux
This allows pam authentication to run for ssh sessions, triggering automation like pam_mkhomedir. Updates #11854 Signed-off-by: Percy Wegmann <percy@tailscale.com>
This commit is contained in:
Percy Wegmann
Percy Wegmann
parent
f1d10c12ac
commit
08a9551a73
5
Makefile
5
Makefile
@ -115,10 +115,7 @@ sshintegrationtest: ## Run the SSH integration tests in various Docker container
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echo "Testing on ubuntu:focal" && docker build --build-arg="BASE=ubuntu:focal" -t ssh-ubuntu-focal ssh/tailssh/testcontainers && \
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echo "Testing on ubuntu:jammy" && docker build --build-arg="BASE=ubuntu:jammy" -t ssh-ubuntu-jammy ssh/tailssh/testcontainers && \
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echo "Testing on ubuntu:mantic" && docker build --build-arg="BASE=ubuntu:mantic" -t ssh-ubuntu-mantic ssh/tailssh/testcontainers && \
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echo "Testing on ubuntu:noble" && docker build --build-arg="BASE=ubuntu:noble" -t ssh-ubuntu-noble ssh/tailssh/testcontainers && \
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echo "Testing on fedora:38" && docker build --build-arg="BASE=dokken/fedora-38" -t ssh-fedora-38 ssh/tailssh/testcontainers && \
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echo "Testing on fedora:39" && docker build --build-arg="BASE=dokken/fedora-39" -t ssh-fedora-39 ssh/tailssh/testcontainers && \
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echo "Testing on fedora:40" && docker build --build-arg="BASE=dokken/fedora-40" -t ssh-fedora-40 ssh/tailssh/testcontainers
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echo "Testing on ubuntu:noble" && docker build --build-arg="BASE=ubuntu:noble" -t ssh-ubuntu-noble ssh/tailssh/testcontainers
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help: ## Show this help
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@echo "\nSpecify a command. The choices are:\n"
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1
go.mod
1
go.mod
@ -14,6 +14,7 @@ require (
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github.com/aws/aws-sdk-go-v2/feature/s3/manager v1.11.64
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github.com/aws/aws-sdk-go-v2/service/s3 v1.33.0
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github.com/aws/aws-sdk-go-v2/service/ssm v1.44.7
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github.com/bramvdbogaerde/go-scp v1.4.0
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github.com/coreos/go-iptables v0.7.1-0.20240112124308-65c67c9f46e6
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github.com/coreos/go-systemd v0.0.0-20191104093116-d3cd4ed1dbcf
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github.com/creack/pty v1.1.21
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2
go.sum
2
go.sum
@ -177,6 +177,8 @@ github.com/blizzy78/varnamelen v0.8.0 h1:oqSblyuQvFsW1hbBHh1zfwrKe3kcSj0rnXkKzsQ
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github.com/blizzy78/varnamelen v0.8.0/go.mod h1:V9TzQZ4fLJ1DSrjVDfl89H7aMnTvKkApdHeyESmyR7k=
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github.com/bombsimon/wsl/v3 v3.4.0 h1:RkSxjT3tmlptwfgEgTgU+KYKLI35p/tviNXNXiL2aNU=
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github.com/bombsimon/wsl/v3 v3.4.0/go.mod h1:KkIB+TXkqy6MvK9BDZVbZxKNYsE1/oLRJbIFtf14qqo=
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github.com/bramvdbogaerde/go-scp v1.4.0 h1:jKMwpwCbcX1KyvDbm/PDJuXcMuNVlLGi0Q0reuzjyKY=
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github.com/bramvdbogaerde/go-scp v1.4.0/go.mod h1:on2aH5AxaFb2G0N5Vsdy6B0Ml7k9HuHSwfo1y0QzAbQ=
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github.com/breml/bidichk v0.2.4 h1:i3yedFWWQ7YzjdZJHnPo9d/xURinSq3OM+gyM43K4/8=
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github.com/breml/bidichk v0.2.4/go.mod h1:7Zk0kRFt1LIZxtQdl9W9JwGAcLTTkOs+tN7wuEYGJ3s=
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github.com/breml/errchkjson v0.3.1 h1:hlIeXuspTyt8Y/UmP5qy1JocGNR00KQHgfaNtRAjoxQ=
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@ -36,6 +36,7 @@
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"golang.org/x/sys/unix"
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"tailscale.com/cmd/tailscaled/childproc"
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"tailscale.com/hostinfo"
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"tailscale.com/tailcfg"
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"tailscale.com/tempfork/gliderlabs/ssh"
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"tailscale.com/types/logger"
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"tailscale.com/version/distro"
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@ -43,18 +44,22 @@
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func init() {
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childproc.Add("ssh", beIncubator)
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childproc.Add("sftp", beSFTP)
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}
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var ptyName = func(f *os.File) (string, error) {
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return "", fmt.Errorf("unimplemented")
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}
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// maybeStartLoginSession starts a new login session for the specified UID.
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// On success, it may return a non-nil close func which must be closed to
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// maybeStartLoginSession informs the system that we are about to log someone
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// in. On success, it may return a non-nil close func which must be closed to
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// release the session.
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// We can only do this if we are running as root.
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// This is best effort to still allow running on machines where
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// we don't support starting sessions, e.g. darwin.
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// See maybeStartLoginSessionLinux.
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var maybeStartLoginSession = func(logf logger.Logf, ia incubatorArgs) (close func() error, err error) {
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return nil, nil
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var maybeStartLoginSession = func(dlogf logger.Logf, ia incubatorArgs) (close func() error) {
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return nil
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}
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// newIncubatorCommand returns a new exec.Cmd configured with
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@ -64,40 +69,39 @@ func init() {
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// exec.CommandContext.
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//
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// The returned Cmd.Env is guaranteed to be nil; the caller populates it.
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func (ss *sshSession) newIncubatorCommand() (cmd *exec.Cmd) {
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func (ss *sshSession) newIncubatorCommand(logf logger.Logf) (cmd *exec.Cmd, err error) {
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defer func() {
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if cmd.Env != nil {
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panic("internal error")
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}
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}()
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var (
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name string
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args []string
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isSFTP bool
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isShell bool
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)
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var isSFTP, isShell bool
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switch ss.Subsystem() {
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case "sftp":
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isSFTP = true
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case "":
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name = ss.conn.localUser.LoginShell()
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if rawCmd := ss.RawCommand(); rawCmd != "" {
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args = append(args, "-c", rawCmd)
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} else {
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isShell = true
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args = append(args, "-l") // login shell
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}
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isShell = ss.RawCommand() == ""
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default:
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panic(fmt.Sprintf("unexpected subsystem: %v", ss.Subsystem()))
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}
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if ss.conn.srv.tailscaledPath == "" {
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// TODO(maisem): this doesn't work with sftp
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return exec.CommandContext(ss.ctx, name, args...)
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if isSFTP {
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// SFTP relies on the embedded Go-based SFTP server in tailscaled,
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// so without tailscaled, we can't serve SFTP.
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return nil, errors.New("no tailscaled found on path, can't serve SFTP")
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}
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loginShell := ss.conn.localUser.LoginShell()
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args := shellArgs(isShell, ss.RawCommand())
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logf("directly running %s %q", loginShell, args)
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return exec.CommandContext(ss.ctx, loginShell, args...), nil
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}
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lu := ss.conn.localUser
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ci := ss.conn.info
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gids := strings.Join(ss.conn.userGroupIDs, ",")
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groups := strings.Join(ss.conn.userGroupIDs, ",")
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remoteUser := ci.uprof.LoginName
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if ci.node.IsTagged() {
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remoteUser = strings.Join(ci.node.Tags().AsSlice(), ",")
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@ -106,9 +110,10 @@ func (ss *sshSession) newIncubatorCommand() (cmd *exec.Cmd) {
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incubatorArgs := []string{
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"be-child",
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"ssh",
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"--login-shell=" + lu.LoginShell(),
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"--uid=" + lu.Uid,
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"--gid=" + lu.Gid,
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"--groups=" + gids,
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"--groups=" + groups,
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"--local-user=" + lu.Username,
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"--remote-user=" + remoteUser,
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"--remote-ip=" + ci.src.Addr().String(),
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@ -116,39 +121,31 @@ func (ss *sshSession) newIncubatorCommand() (cmd *exec.Cmd) {
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"--tty-name=", // updated in-place by startWithPTY
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}
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forceV1Behavior := ss.conn.srv.lb.NetMap().HasCap(tailcfg.NodeAttrSSHBehaviorV1)
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if forceV1Behavior {
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incubatorArgs = append(incubatorArgs, "--force-v1-behavior")
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}
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if debugTest.Load() {
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incubatorArgs = append(incubatorArgs, "--debug-test")
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}
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if isSFTP {
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incubatorArgs = append(incubatorArgs, "--sftp")
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} else {
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if isShell {
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switch {
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case isSFTP:
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// Note that we include both the `--sftp` flag and a command to launch
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// tailscaled as `be-child sftp`. If login or su is available, and
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// we're not running with tailcfg.NodeAttrSSHBehaviorV1, this will
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// result in serving SFTP within a login shell, with full PAM
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// integration. Otherwise, we'll serve SFTP in the incubator process
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// with no PAM integration.
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incubatorArgs = append(incubatorArgs, "--sftp", fmt.Sprintf("--cmd=%s be-child sftp", ss.conn.srv.tailscaledPath))
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case isShell:
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incubatorArgs = append(incubatorArgs, "--shell")
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default:
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incubatorArgs = append(incubatorArgs, "--cmd="+ss.RawCommand())
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}
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// Only the macOS version of the login command supports executing a
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// command, all other versions only support launching a shell
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// without taking any arguments.
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shouldUseLoginCmd := isShell || runtime.GOOS == "darwin"
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if hostinfo.IsSELinuxEnforcing() {
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// If we're running on a SELinux-enabled system, the login
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// command will be unable to set the correct context for the
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// shell. Fall back to using the incubator to launch the shell.
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// See http://github.com/tailscale/tailscale/issues/4908.
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shouldUseLoginCmd = false
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}
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if shouldUseLoginCmd {
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if lp, err := exec.LookPath("login"); err == nil {
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incubatorArgs = append(incubatorArgs, "--login-cmd="+lp)
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}
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}
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incubatorArgs = append(incubatorArgs, "--cmd="+name)
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if len(args) > 0 {
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incubatorArgs = append(incubatorArgs, "--")
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incubatorArgs = append(incubatorArgs, args...)
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}
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}
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return exec.CommandContext(ss.ctx, ss.conn.srv.tailscaledPath, incubatorArgs...)
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return exec.CommandContext(ss.ctx, ss.conn.srv.tailscaledPath, incubatorArgs...), nil
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}
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var debugIncubator bool
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@ -170,51 +167,60 @@ func (stdRWC) Close() error {
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}
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type incubatorArgs struct {
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loginShell string
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uid int
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gid int
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groups string
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gids []int
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localUser string
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remoteUser string
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remoteIP string
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ttyName string
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hasTTY bool
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cmdName string
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cmd string
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isSFTP bool
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isShell bool
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loginCmdPath string
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cmdArgs []string
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forceV1Behavior bool
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debugTest bool
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}
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func parseIncubatorArgs(args []string) (a incubatorArgs) {
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func parseIncubatorArgs(args []string) (incubatorArgs, error) {
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var ia incubatorArgs
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var groups string
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flags := flag.NewFlagSet("", flag.ExitOnError)
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flags.IntVar(&a.uid, "uid", 0, "the uid of local-user")
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flags.IntVar(&a.gid, "gid", 0, "the gid of local-user")
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flags.StringVar(&a.groups, "groups", "", "comma-separated list of gids of local-user")
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flags.StringVar(&a.localUser, "local-user", "", "the user to run as")
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flags.StringVar(&a.remoteUser, "remote-user", "", "the remote user/tags")
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flags.StringVar(&a.remoteIP, "remote-ip", "", "the remote Tailscale IP")
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flags.StringVar(&a.ttyName, "tty-name", "", "the tty name (pts/3)")
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flags.BoolVar(&a.hasTTY, "has-tty", false, "is the output attached to a tty")
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flags.StringVar(&a.cmdName, "cmd", "", "the cmd to launch (ignored in sftp mode)")
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flags.BoolVar(&a.isShell, "shell", false, "is launching a shell (with no cmds)")
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flags.BoolVar(&a.isSFTP, "sftp", false, "run sftp server (cmd is ignored)")
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flags.StringVar(&a.loginCmdPath, "login-cmd", "", "the path to `login` cmd")
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flags.BoolVar(&a.debugTest, "debug-test", false, "should debug in test mode")
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flags.StringVar(&ia.loginShell, "login-shell", "", "path to the user's preferred login shell")
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flags.IntVar(&ia.uid, "uid", 0, "the uid of local-user")
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flags.IntVar(&ia.gid, "gid", 0, "the gid of local-user")
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flags.StringVar(&groups, "groups", "", "comma-separated list of gids of local-user")
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flags.StringVar(&ia.localUser, "local-user", "", "the user to run as")
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flags.StringVar(&ia.remoteUser, "remote-user", "", "the remote user/tags")
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flags.StringVar(&ia.remoteIP, "remote-ip", "", "the remote Tailscale IP")
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flags.StringVar(&ia.ttyName, "tty-name", "", "the tty name (pts/3)")
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flags.BoolVar(&ia.hasTTY, "has-tty", false, "is the output attached to a tty")
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flags.StringVar(&ia.cmd, "cmd", "", "the cmd to launch, including all arguments (ignored in sftp mode)")
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flags.BoolVar(&ia.isShell, "shell", false, "is launching a shell (with no cmds)")
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flags.BoolVar(&ia.isSFTP, "sftp", false, "run sftp server (cmd is ignored)")
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flags.BoolVar(&ia.forceV1Behavior, "force-v1-behavior", false, "allow falling back to the su command if login is unavailable")
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flags.BoolVar(&ia.debugTest, "debug-test", false, "should debug in test mode")
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flags.Parse(args)
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a.cmdArgs = flags.Args()
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return a
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for _, g := range strings.Split(groups, ",") {
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gid, err := strconv.Atoi(g)
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if err != nil {
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return ia, fmt.Errorf("unable to parse group id %q: %w", g, err)
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}
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ia.gids = append(ia.gids, gid)
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}
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return ia, nil
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}
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// beIncubator is the entrypoint to the `tailscaled be-child ssh` subcommand.
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// It is responsible for informing the system of a new login session for the user.
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// This is sometimes necessary for mounting home directories and decrypting file
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// systems.
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// It is responsible for informing the system of a new login session for the
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// user. This is sometimes necessary for mounting home directories and
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// decrypting file systems.
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//
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// Tailscaled launches the incubator as the same user as it was
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// launched as. The incubator then registers a new session with the
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// OS, sets its UID and groups to the specified `--uid`, `--gid` and
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// `--groups` and then launches the requested `--cmd`.
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// Tailscaled launches the incubator as the same user as it was launched as.
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func beIncubator(args []string) error {
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// To defend against issues like https://golang.org/issue/1435,
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// defensively lock our current goroutine's thread to the current
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@ -226,22 +232,25 @@ func beIncubator(args []string) error {
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runtime.LockOSThread()
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defer runtime.UnlockOSThread()
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ia := parseIncubatorArgs(args)
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ia, err := parseIncubatorArgs(args)
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if err != nil {
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return err
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}
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if ia.isSFTP && ia.isShell {
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return fmt.Errorf("--sftp and --shell are mutually exclusive")
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}
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logf := logger.Discard
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dlogf := logger.Discard
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if debugIncubator {
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// We don't own stdout or stderr, so the only place we can log is syslog.
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if sl, err := syslog.New(syslog.LOG_INFO|syslog.LOG_DAEMON, "tailscaled-ssh"); err == nil {
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logf = log.New(sl, "", 0).Printf
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dlogf = log.New(sl, "", 0).Printf
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}
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} else if ia.debugTest {
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// In testing, we don't always have syslog, log to a temp file
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// In testing, we don't always have syslog, so log to a temp file.
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if logFile, err := os.OpenFile("/tmp/tailscalessh.log", os.O_APPEND|os.O_WRONLY, 0666); err == nil {
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lf := log.New(logFile, "", 0)
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logf = func(msg string, args ...any) {
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dlogf = func(msg string, args ...any) {
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lf.Printf(msg, args...)
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logFile.Sync()
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}
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@ -249,41 +258,55 @@ func beIncubator(args []string) error {
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}
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}
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euid := os.Geteuid()
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runningAsRoot := euid == 0
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if runningAsRoot && ia.loginCmdPath != "" {
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// Check if we can exec into the login command instead of trying to
|
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// incubate ourselves.
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if la := ia.loginArgs(); la != nil {
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return unix.Exec(ia.loginCmdPath, la, os.Environ())
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}
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if !shouldAttemptLoginShell(dlogf, ia) {
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dlogf("not attempting login shell")
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return handleInProcess(dlogf, ia)
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}
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|
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// Inform the system that we are about to log someone in.
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// We can only do this if we are running as root.
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||||
// This is best effort to still allow running on machines where
|
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// we don't support starting sessions, e.g. darwin.
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sessionCloser, err := maybeStartLoginSession(logf, ia)
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if err == nil && sessionCloser != nil {
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// First try the login command
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if err := tryExecLogin(dlogf, ia); err != nil {
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return err
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}
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// If we got here, we weren't able to use login (because tryExecLogin
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// returned without replacing the running process), maybe we can use
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// su.
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if handled, err := trySU(dlogf, ia); handled {
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return err
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} else {
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dlogf("not attempting su")
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return handleInProcess(dlogf, ia)
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}
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}
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|
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func handleInProcess(dlogf logger.Logf, ia incubatorArgs) error {
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if ia.isSFTP {
|
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return handleSFTPInProcess(dlogf, ia)
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}
|
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return handleSSHInProcess(dlogf, ia)
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}
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|
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func handleSFTPInProcess(dlogf logger.Logf, ia incubatorArgs) error {
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dlogf("handling sftp")
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|
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sessionCloser := maybeStartLoginSession(dlogf, ia)
|
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if sessionCloser != nil {
|
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defer sessionCloser()
|
||||
}
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|
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var groupIDs []int
|
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for _, g := range strings.Split(ia.groups, ",") {
|
||||
gid, err := strconv.ParseInt(g, 10, 32)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
groupIDs = append(groupIDs, int(gid))
|
||||
}
|
||||
|
||||
if err := dropPrivileges(logf, ia.uid, ia.gid, groupIDs); err != nil {
|
||||
if err := dropPrivileges(dlogf, ia); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
if ia.isSFTP {
|
||||
logf("handling sftp")
|
||||
return serveSFTP()
|
||||
}
|
||||
|
||||
// beSFTP serves SFTP in-process.
|
||||
func beSFTP(args []string) error {
|
||||
return serveSFTP()
|
||||
}
|
||||
|
||||
func serveSFTP() error {
|
||||
server, err := sftp.NewServer(stdRWC{})
|
||||
if err != nil {
|
||||
return err
|
||||
@ -294,27 +317,174 @@ func beIncubator(args []string) error {
|
||||
return err
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// shouldAttemptLoginShell decides whether we should attempt to get a full
|
||||
// login shell with the login or su commands. We will attempt a login shell
|
||||
// if all of the following conditions are met.
|
||||
//
|
||||
// - We are running as root
|
||||
// - This is not an SELinuxEnforcing host
|
||||
//
|
||||
// The last condition exists because if we're running on a SELinux-enabled
|
||||
// system, neiher login nor su will be able to set the correct context for the
|
||||
// shell. So, we don't bother trying to run them and instead fall back to using
|
||||
// the incubator to launch the shell.
|
||||
// See http://github.com/tailscale/tailscale/issues/4908.
|
||||
func shouldAttemptLoginShell(dlogf logger.Logf, ia incubatorArgs) bool {
|
||||
if ia.forceV1Behavior && ia.isSFTP {
|
||||
// v1 behavior did not run SFTP within a login shell.
|
||||
dlogf("Forcing v1 behavior, won't use login shell for SFTP")
|
||||
return false
|
||||
}
|
||||
|
||||
cmd := exec.Command(ia.cmdName, ia.cmdArgs...)
|
||||
cmd.Stdin = os.Stdin
|
||||
cmd.Stdout = os.Stdout
|
||||
cmd.Stderr = os.Stderr
|
||||
cmd.Env = os.Environ()
|
||||
return runningAsRoot() && !hostinfo.IsSELinuxEnforcing()
|
||||
}
|
||||
|
||||
if ia.hasTTY {
|
||||
// If we were launched with a tty then we should
|
||||
// mark that as the ctty of the child. However,
|
||||
// as the ctty is being passed from the parent
|
||||
// we set the child to foreground instead which
|
||||
// also passes the ctty.
|
||||
// However, we can not do this if never had a tty to
|
||||
// begin with.
|
||||
cmd.SysProcAttr = &syscall.SysProcAttr{
|
||||
Foreground: true,
|
||||
func runningAsRoot() bool {
|
||||
euid := os.Geteuid()
|
||||
return euid == 0
|
||||
}
|
||||
|
||||
// tryExecLogin attempts to handle the ssh session by creating a full login
|
||||
// shell using the login command. If it never tried, it returns nil. If it
|
||||
// failed to do so, it returns an error.
|
||||
//
|
||||
// Creating a login shell in this way allows us to register the remote IP of
|
||||
// the login session, trigger PAM authentication, and get the "remote" PAM
|
||||
// profile.
|
||||
//
|
||||
// However, login is subject to some limitations.
|
||||
//
|
||||
// 1. login cannot be used to execute commands except on macOS.
|
||||
// 2. On Linux and BSD, login requires a TTY to keep running.
|
||||
//
|
||||
// In these cases, tryExecLogin returns (false, nil) to indicate that processing
|
||||
// should fall through to other methods, such as using the su command.
|
||||
//
|
||||
// Note that this uses unix.Exec to replace the current process, so in cases
|
||||
// where we actually do run login, no subsequent Go code will execute.
|
||||
func tryExecLogin(dlogf logger.Logf, ia incubatorArgs) error {
|
||||
// Only the macOS version of the login command supports executing a
|
||||
// command, all other versions only support launching a shell without
|
||||
// taking any arguments.
|
||||
if !ia.isShell && runtime.GOOS != "darwin" {
|
||||
dlogf("won't use login because we're not in a shell or on macOS")
|
||||
return nil
|
||||
}
|
||||
|
||||
switch runtime.GOOS {
|
||||
case "linux", "freebsd", "openbsd":
|
||||
if !ia.hasTTY {
|
||||
dlogf("can't use login because of missing TTY")
|
||||
// We can only use the login command if a shell was requested with
|
||||
// a TTY. If there is no TTY, login exits immediately, which
|
||||
// breaks things like mosh and VSCode.
|
||||
return nil
|
||||
}
|
||||
}
|
||||
err = cmd.Run()
|
||||
|
||||
loginCmdPath, err := exec.LookPath("login")
|
||||
if err != nil {
|
||||
dlogf("failed to get login args: %s", err)
|
||||
return nil
|
||||
}
|
||||
loginArgs := ia.loginArgs(loginCmdPath)
|
||||
dlogf("logging in with %s %+v", loginCmdPath, loginArgs)
|
||||
// replace the running process
|
||||
return unix.Exec(loginCmdPath, loginArgs, os.Environ())
|
||||
}
|
||||
|
||||
// trySU attempts to start a login shell using su. If su is available and
|
||||
// supports the necessary arguments, this returns true, plus the result of
|
||||
// executing su. Otherwise, it returns (false, nil).
|
||||
//
|
||||
// Creating a login shell in this way allows us to trigger PAM authentication
|
||||
// and get the "login" PAM profile.
|
||||
//
|
||||
// Unlike login, su often does not require a TTY, so on Linux hosts that have
|
||||
// an su command which accepts the right flags, we'll use su instead of login
|
||||
// when no TTY is available.
|
||||
func trySU(dlogf logger.Logf, ia incubatorArgs) (handled bool, err error) {
|
||||
if ia.forceV1Behavior {
|
||||
// v1 behavior did not use su.
|
||||
dlogf("Forcing v1 behavior, won't use su")
|
||||
return false, nil
|
||||
}
|
||||
|
||||
su := findSU(dlogf, ia)
|
||||
if su == "" {
|
||||
return false, nil
|
||||
}
|
||||
|
||||
sessionCloser := maybeStartLoginSession(dlogf, ia)
|
||||
if sessionCloser != nil {
|
||||
defer sessionCloser()
|
||||
}
|
||||
|
||||
loginArgs := []string{"-l", ia.localUser}
|
||||
if ia.cmd != "" {
|
||||
// Note - unlike the login command, su allows using both -l and -c.
|
||||
loginArgs = append(loginArgs, "-c", ia.cmd)
|
||||
}
|
||||
|
||||
dlogf("logging in with %s %q", su, loginArgs)
|
||||
cmd := newCommand(ia.hasTTY, su, loginArgs)
|
||||
return true, cmd.Run()
|
||||
}
|
||||
|
||||
// findSU attempts to find an su command which supports the -l and -c flags.
|
||||
// This actually calls the su command, which can cause side effects like
|
||||
// triggering pam_mkhomedir. If a suitable su is not available, this returns
|
||||
// "".
|
||||
func findSU(dlogf logger.Logf, ia incubatorArgs) string {
|
||||
// Currently, we only support falling back to su on Linux. This
|
||||
// potentially could work on BSDs as well, but requires testing.
|
||||
if runtime.GOOS != "linux" {
|
||||
return ""
|
||||
}
|
||||
|
||||
// gokrazy doesn't include su. And, if someone installs a breakglass/
|
||||
// debugging package on gokrazy, we don't want to use its su.
|
||||
if distro.Get() == distro.Gokrazy {
|
||||
return ""
|
||||
}
|
||||
|
||||
su, err := exec.LookPath("su")
|
||||
if err != nil {
|
||||
dlogf("can't find su command: %v", err)
|
||||
return ""
|
||||
}
|
||||
|
||||
// First try to execute su -l <user> -c true to make sure su supports the
|
||||
// necessary arguments.
|
||||
err = exec.Command(su, "-l", ia.localUser, "-c", "true").Run()
|
||||
if err != nil {
|
||||
dlogf("su check failed: %s", err)
|
||||
return ""
|
||||
}
|
||||
|
||||
return su
|
||||
}
|
||||
|
||||
// handleSSHInProcess is a last resort if we couldn't use login or su. It
|
||||
// registers a new session with the OS, sets its UID, GID and groups to the
|
||||
// specified values, and then launches the requested `--cmd` in the user's
|
||||
// login shell.
|
||||
func handleSSHInProcess(dlogf logger.Logf, ia incubatorArgs) error {
|
||||
sessionCloser := maybeStartLoginSession(dlogf, ia)
|
||||
if sessionCloser != nil {
|
||||
defer sessionCloser()
|
||||
}
|
||||
|
||||
if err := dropPrivileges(dlogf, ia); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
args := shellArgs(ia.isShell, ia.cmd)
|
||||
dlogf("running %s %q", ia.loginShell, args)
|
||||
cmd := newCommand(ia.hasTTY, ia.loginShell, args)
|
||||
err := cmd.Run()
|
||||
if ee, ok := err.(*exec.ExitError); ok {
|
||||
ps := ee.ProcessState
|
||||
code := ps.ExitCode()
|
||||
@ -330,6 +500,26 @@ func beIncubator(args []string) error {
|
||||
return err
|
||||
}
|
||||
|
||||
func newCommand(hasTTY bool, cmdPath string, cmdArgs []string) *exec.Cmd {
|
||||
cmd := exec.Command(cmdPath, cmdArgs...)
|
||||
cmd.Stdin = os.Stdin
|
||||
cmd.Stdout = os.Stdout
|
||||
cmd.Stderr = os.Stderr
|
||||
cmd.Env = os.Environ()
|
||||
|
||||
if hasTTY {
|
||||
// If we were launched with a tty then we should mark that as the ctty
|
||||
// of the child. However, as the ctty is being passed from the parent
|
||||
// we set the child to foreground instead which also passes the ctty.
|
||||
// However, we can not do this if never had a tty to begin with.
|
||||
cmd.SysProcAttr = &syscall.SysProcAttr{
|
||||
Foreground: true,
|
||||
}
|
||||
}
|
||||
|
||||
return cmd
|
||||
}
|
||||
|
||||
const (
|
||||
// This controls whether we assert that our privileges were dropped
|
||||
// using geteuid/getegid; it's a const and not an envknob because the
|
||||
@ -344,19 +534,26 @@ func beIncubator(args []string) error {
|
||||
assertPrivilegesWereDroppedByAttemptingToUnDrop = false
|
||||
)
|
||||
|
||||
// dropPrivileges contains all the logic for dropping privileges to a different
|
||||
// dropPrivileges calls doDropPrivileges with uid, gid, and gids from the given
|
||||
// incubatorArgs.
|
||||
func dropPrivileges(dlogf logger.Logf, ia incubatorArgs) error {
|
||||
return doDropPrivileges(dlogf, ia.uid, ia.gid, ia.gids)
|
||||
}
|
||||
|
||||
// doDropPrivileges contains all the logic for dropping privileges to a different
|
||||
// UID, GID, and set of supplementary groups. This function is
|
||||
// security-sensitive and ordering-dependent; please be very cautious if/when
|
||||
// refactoring.
|
||||
//
|
||||
// WARNING: if you change this function, you *MUST* run the TestDropPrivileges
|
||||
// WARNING: if you change this function, you *MUST* run the TestDoDropPrivileges
|
||||
// test in this package as root on at least Linux, FreeBSD and Darwin. This can
|
||||
// be done by running:
|
||||
//
|
||||
// go test -c ./ssh/tailssh/ && sudo ./tailssh.test -test.v -test.run TestDropPrivileges
|
||||
func dropPrivileges(logf logger.Logf, wantUid, wantGid int, supplementaryGroups []int) error {
|
||||
// go test -c ./ssh/tailssh/ && sudo ./tailssh.test -test.v -test.run TestDoDropPrivileges
|
||||
func doDropPrivileges(dlogf logger.Logf, wantUid, wantGid int, supplementaryGroups []int) error {
|
||||
dlogf("dropping privileges")
|
||||
fatalf := func(format string, args ...any) {
|
||||
logf("[unexpected] error dropping privileges: "+format, args...)
|
||||
dlogf("[unexpected] error dropping privileges: "+format, args...)
|
||||
os.Exit(1)
|
||||
}
|
||||
|
||||
@ -448,7 +645,11 @@ func dropPrivileges(logf logger.Logf, wantUid, wantGid int, supplementaryGroups
|
||||
//
|
||||
// It sets ss.cmd, stdin, stdout, and stderr.
|
||||
func (ss *sshSession) launchProcess() error {
|
||||
ss.cmd = ss.newIncubatorCommand()
|
||||
var err error
|
||||
ss.cmd, err = ss.newIncubatorCommand(ss.logf)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
cmd := ss.cmd
|
||||
homeDir := ss.conn.localUser.HomeDir
|
||||
@ -749,18 +950,11 @@ func fileExists(path string) bool {
|
||||
}
|
||||
|
||||
// loginArgs returns the arguments to use to exec the login binary.
|
||||
// It returns nil if the login binary should not be used.
|
||||
// The login binary is only used:
|
||||
// - on darwin, if the client is requesting a shell or a command.
|
||||
// - on linux and BSD, if the client is requesting a shell with a TTY.
|
||||
func (ia *incubatorArgs) loginArgs() []string {
|
||||
if ia.isSFTP {
|
||||
return nil
|
||||
}
|
||||
func (ia *incubatorArgs) loginArgs(loginCmdPath string) []string {
|
||||
switch runtime.GOOS {
|
||||
case "darwin":
|
||||
args := []string{
|
||||
ia.loginCmdPath,
|
||||
loginCmdPath,
|
||||
"-f", // already authenticated
|
||||
|
||||
// login typically discards the previous environment, but we want to
|
||||
@ -773,39 +967,35 @@ func (ia *incubatorArgs) loginArgs() []string {
|
||||
if !ia.hasTTY {
|
||||
args[2] = "-pq" // -q is "quiet" which suppresses the login banner
|
||||
}
|
||||
if ia.cmdName != "" {
|
||||
args = append(args, ia.cmdName)
|
||||
args = append(args, ia.cmdArgs...)
|
||||
if ia.cmd != "" {
|
||||
args = append(args, ia.loginShell, "-c", ia.cmd)
|
||||
}
|
||||
|
||||
return args
|
||||
case "linux":
|
||||
if !ia.isShell || !ia.hasTTY {
|
||||
// We can only use login command if a shell was requested with a TTY. If
|
||||
// there is no TTY, login exits immediately, which breaks things likes
|
||||
// mosh and VSCode.
|
||||
return nil
|
||||
}
|
||||
if distro.Get() == distro.Arch && !fileExists("/etc/pam.d/remote") {
|
||||
// See https://github.com/tailscale/tailscale/issues/4924
|
||||
//
|
||||
// Arch uses a different login binary that makes the -h flag set the PAM
|
||||
// service to "remote". So if they don't have that configured, don't
|
||||
// pass -h.
|
||||
return []string{ia.loginCmdPath, "-f", ia.localUser, "-p"}
|
||||
return []string{loginCmdPath, "-f", ia.localUser, "-p"}
|
||||
}
|
||||
return []string{ia.loginCmdPath, "-f", ia.localUser, "-h", ia.remoteIP, "-p"}
|
||||
return []string{loginCmdPath, "-f", ia.localUser, "-h", ia.remoteIP, "-p"}
|
||||
case "freebsd", "openbsd":
|
||||
if !ia.isShell || !ia.hasTTY {
|
||||
// We can only use login command if a shell was requested with a TTY. If
|
||||
// there is no TTY, login exits immediately, which breaks things likes
|
||||
// mosh and VSCode.
|
||||
return nil
|
||||
}
|
||||
return []string{ia.loginCmdPath, "-fp", "-h", ia.remoteIP, ia.localUser}
|
||||
return []string{loginCmdPath, "-fp", "-h", ia.remoteIP, ia.localUser}
|
||||
}
|
||||
panic("unimplemented")
|
||||
}
|
||||
|
||||
func shellArgs(isShell bool, cmd string) []string {
|
||||
if isShell {
|
||||
return []string{"-l"}
|
||||
} else {
|
||||
return []string{"-c", cmd}
|
||||
}
|
||||
}
|
||||
|
||||
func setGroups(groupIDs []int) error {
|
||||
if runtime.GOOS == "darwin" && len(groupIDs) > 16 {
|
||||
// darwin returns "invalid argument" if more than 16 groups are passed to syscall.Setgroups
|
||||
|
||||
@ -146,11 +146,11 @@ func releaseSession(sessionID string) error {
|
||||
}
|
||||
|
||||
// maybeStartLoginSessionLinux is the linux implementation of maybeStartLoginSession.
|
||||
func maybeStartLoginSessionLinux(logf logger.Logf, ia incubatorArgs) (func() error, error) {
|
||||
func maybeStartLoginSessionLinux(dlogf logger.Logf, ia incubatorArgs) func() error {
|
||||
if os.Geteuid() != 0 {
|
||||
return nil, nil
|
||||
return nil
|
||||
}
|
||||
logf("starting session for user %d", ia.uid)
|
||||
dlogf("starting session for user %d", ia.uid)
|
||||
// The only way we can actually start a new session is if we are
|
||||
// running outside one and are root, which is typically the case
|
||||
// for systemd managed tailscaled.
|
||||
@ -160,14 +160,14 @@ func maybeStartLoginSessionLinux(logf logger.Logf, ia incubatorArgs) (func() err
|
||||
// We can look at the DBus GetSessionByPID API.
|
||||
// https://www.freedesktop.org/software/systemd/man/org.freedesktop.login1.html
|
||||
// For now best effort is fine.
|
||||
logf("ssh: failed to CreateSession for user %q (%d) %v", ia.localUser, ia.uid, err)
|
||||
return nil, nil
|
||||
dlogf("ssh: failed to CreateSession for user %q (%d) %v", ia.localUser, ia.uid, err)
|
||||
return nil
|
||||
}
|
||||
os.Setenv("DBUS_SESSION_BUS_ADDRESS", fmt.Sprintf("unix:path=%v/bus", resp.runtimePath))
|
||||
if !resp.existing {
|
||||
return func() error {
|
||||
return releaseSession(resp.sessionID)
|
||||
}, nil
|
||||
}
|
||||
return nil, nil
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
@ -23,7 +23,7 @@
|
||||
"tailscale.com/types/logger"
|
||||
)
|
||||
|
||||
func TestDropPrivileges(t *testing.T) {
|
||||
func TestDoDropPrivileges(t *testing.T) {
|
||||
type SubprocInput struct {
|
||||
UID int
|
||||
GID int
|
||||
@ -49,7 +49,7 @@ type SubprocOutput struct {
|
||||
f := os.NewFile(3, "out.json")
|
||||
|
||||
// We're in our subprocess; actually drop privileges now.
|
||||
dropPrivileges(t.Logf, input.UID, input.GID, input.AdditionalGroups)
|
||||
doDropPrivileges(t.Logf, input.UID, input.GID, input.AdditionalGroups)
|
||||
|
||||
additional, _ := syscall.Getgroups()
|
||||
|
||||
|
||||
@ -8,6 +8,7 @@
|
||||
|
||||
import (
|
||||
"bufio"
|
||||
"context"
|
||||
"crypto/ecdsa"
|
||||
"crypto/ed25519"
|
||||
"crypto/elliptic"
|
||||
@ -28,6 +29,7 @@
|
||||
"testing"
|
||||
"time"
|
||||
|
||||
"github.com/bramvdbogaerde/go-scp"
|
||||
"github.com/google/go-cmp/cmp"
|
||||
"github.com/pkg/sftp"
|
||||
gossh "github.com/tailscale/golang-x-crypto/ssh"
|
||||
@ -36,6 +38,7 @@
|
||||
"tailscale.com/tailcfg"
|
||||
"tailscale.com/types/key"
|
||||
"tailscale.com/types/netmap"
|
||||
"tailscale.com/util/set"
|
||||
)
|
||||
|
||||
// This file contains integration tests of the SSH functionality. These tests
|
||||
@ -58,7 +61,7 @@ func TestMain(m *testing.M) {
|
||||
file.Close()
|
||||
|
||||
// Tail our log file.
|
||||
cmd := exec.Command("tail", "-f", "/tmp/tailscalessh.log")
|
||||
cmd := exec.Command("tail", "-F", "/tmp/tailscalessh.log")
|
||||
|
||||
r, err := cmd.StdoutPipe()
|
||||
if err != nil {
|
||||
@ -77,6 +80,12 @@ func TestMain(m *testing.M) {
|
||||
if err != nil {
|
||||
return
|
||||
}
|
||||
defer func() {
|
||||
// tail -f has a default sleep interval of 1 second, so it takes a
|
||||
// moment for it to finish reading our log file after we've terminated.
|
||||
// So, wait a bit to let it catch up.
|
||||
time.Sleep(2 * time.Second)
|
||||
}()
|
||||
|
||||
m.Run()
|
||||
}
|
||||
@ -95,18 +104,38 @@ func TestIntegrationSSH(t *testing.T) {
|
||||
tests := []struct {
|
||||
cmd string
|
||||
want []string
|
||||
forceV1Behavior bool
|
||||
skip bool
|
||||
}{
|
||||
{
|
||||
cmd: "id",
|
||||
want: []string{"testuser", "groupone", "grouptwo"},
|
||||
forceV1Behavior: false,
|
||||
},
|
||||
{
|
||||
cmd: "id",
|
||||
want: []string{"testuser", "groupone", "grouptwo"},
|
||||
forceV1Behavior: true,
|
||||
},
|
||||
{
|
||||
cmd: "pwd",
|
||||
want: []string{homeDir},
|
||||
skip: !fallbackToSUAvailable(),
|
||||
forceV1Behavior: false,
|
||||
},
|
||||
{
|
||||
cmd: "echo 'hello'",
|
||||
want: []string{"hello"},
|
||||
skip: !fallbackToSUAvailable(),
|
||||
forceV1Behavior: false,
|
||||
},
|
||||
}
|
||||
|
||||
for _, test := range tests {
|
||||
if test.skip {
|
||||
continue
|
||||
}
|
||||
|
||||
// run every test both without and with a shell
|
||||
for _, shell := range []bool{false, true} {
|
||||
shellQualifier := "no_shell"
|
||||
@ -114,8 +143,13 @@ func TestIntegrationSSH(t *testing.T) {
|
||||
shellQualifier = "shell"
|
||||
}
|
||||
|
||||
t.Run(fmt.Sprintf("%s_%s", test.cmd, shellQualifier), func(t *testing.T) {
|
||||
s := testSession(t)
|
||||
versionQualifier := "v2"
|
||||
if test.forceV1Behavior {
|
||||
versionQualifier = "v1"
|
||||
}
|
||||
|
||||
t.Run(fmt.Sprintf("%s_%s_%s", test.cmd, shellQualifier, versionQualifier), func(t *testing.T) {
|
||||
s := testSession(t, test.forceV1Behavior)
|
||||
|
||||
if shell {
|
||||
err := s.RequestPty("xterm", 40, 80, ssh.TerminalModes{
|
||||
@ -124,11 +158,19 @@ func TestIntegrationSSH(t *testing.T) {
|
||||
ssh.TTY_OP_OSPEED: 14400,
|
||||
})
|
||||
if err != nil {
|
||||
t.Fatalf("unable to request shell: %s", err)
|
||||
}
|
||||
t.Fatalf("unable to request PTY: %s", err)
|
||||
}
|
||||
|
||||
got := s.run(t, test.cmd)
|
||||
err = s.Shell()
|
||||
if err != nil {
|
||||
t.Fatalf("unable to request shell: %s", err)
|
||||
}
|
||||
|
||||
// Read the shell prompt
|
||||
s.read()
|
||||
}
|
||||
|
||||
got := s.run(t, test.cmd, shell)
|
||||
for _, want := range test.want {
|
||||
if !strings.Contains(got, want) {
|
||||
t.Errorf("%q does not contain %q", got, want)
|
||||
@ -145,10 +187,19 @@ func TestIntegrationSFTP(t *testing.T) {
|
||||
debugTest.Store(false)
|
||||
})
|
||||
|
||||
filePath := "/tmp/sftptest.dat"
|
||||
for _, forceV1Behavior := range []bool{false, true} {
|
||||
name := "v2"
|
||||
if forceV1Behavior {
|
||||
name = "v1"
|
||||
}
|
||||
t.Run(name, func(t *testing.T) {
|
||||
filePath := "/home/testuser/sftptest.dat"
|
||||
if forceV1Behavior || !fallbackToSUAvailable() {
|
||||
filePath = "/tmp/sftptest.dat"
|
||||
}
|
||||
wantText := "hello world"
|
||||
|
||||
cl := testClient(t)
|
||||
cl := testClient(t, forceV1Behavior)
|
||||
scl, err := sftp.NewClient(cl)
|
||||
if err != nil {
|
||||
t.Fatalf("can't get sftp client: %s", err)
|
||||
@ -181,12 +232,88 @@ func TestIntegrationSFTP(t *testing.T) {
|
||||
}
|
||||
|
||||
s := testSessionFor(t, cl)
|
||||
got := s.run(t, "ls -l "+filePath)
|
||||
got := s.run(t, "ls -l "+filePath, false)
|
||||
if !strings.Contains(got, "testuser") {
|
||||
t.Fatalf("unexpected file owner user: %s", got)
|
||||
} else if !strings.Contains(got, "testuser") {
|
||||
t.Fatalf("unexpected file owner group: %s", got)
|
||||
}
|
||||
})
|
||||
}
|
||||
}
|
||||
|
||||
func TestIntegrationSCP(t *testing.T) {
|
||||
debugTest.Store(true)
|
||||
t.Cleanup(func() {
|
||||
debugTest.Store(false)
|
||||
})
|
||||
|
||||
for _, forceV1Behavior := range []bool{false, true} {
|
||||
name := "v2"
|
||||
if forceV1Behavior {
|
||||
name = "v1"
|
||||
}
|
||||
t.Run(name, func(t *testing.T) {
|
||||
filePath := "/home/testuser/scptest.dat"
|
||||
if !fallbackToSUAvailable() {
|
||||
filePath = "/tmp/scptest.dat"
|
||||
}
|
||||
wantText := "hello world"
|
||||
|
||||
cl := testClient(t, forceV1Behavior)
|
||||
scl, err := scp.NewClientBySSH(cl)
|
||||
if err != nil {
|
||||
t.Fatalf("can't get sftp client: %s", err)
|
||||
}
|
||||
|
||||
err = scl.Copy(context.Background(), strings.NewReader(wantText), filePath, "0644", int64(len(wantText)))
|
||||
if err != nil {
|
||||
t.Fatalf("can't create file: %s", err)
|
||||
}
|
||||
|
||||
outfile, err := os.CreateTemp("", "")
|
||||
if err != nil {
|
||||
t.Fatalf("can't create temp file: %s", err)
|
||||
}
|
||||
err = scl.CopyFromRemote(context.Background(), outfile, filePath)
|
||||
if err != nil {
|
||||
t.Fatalf("can't copy file from remote: %s", err)
|
||||
}
|
||||
outfile.Close()
|
||||
|
||||
gotText, err := os.ReadFile(outfile.Name())
|
||||
if err != nil {
|
||||
t.Fatalf("can't read file: %s", err)
|
||||
}
|
||||
if diff := cmp.Diff(string(gotText), wantText); diff != "" {
|
||||
t.Fatalf("unexpected file contents (-got +want):\n%s", diff)
|
||||
}
|
||||
|
||||
s := testSessionFor(t, cl)
|
||||
got := s.run(t, "ls -l "+filePath, false)
|
||||
if !strings.Contains(got, "testuser") {
|
||||
t.Fatalf("unexpected file owner user: %s", got)
|
||||
} else if !strings.Contains(got, "testuser") {
|
||||
t.Fatalf("unexpected file owner group: %s", got)
|
||||
}
|
||||
})
|
||||
}
|
||||
}
|
||||
|
||||
func fallbackToSUAvailable() bool {
|
||||
if runtime.GOOS != "linux" {
|
||||
return false
|
||||
}
|
||||
|
||||
_, err := exec.LookPath("su")
|
||||
if err != nil {
|
||||
return false
|
||||
}
|
||||
|
||||
// Some operating systems like Fedora seem to require login to be present
|
||||
// in order for su to work.
|
||||
_, err = exec.LookPath("login")
|
||||
return err == nil
|
||||
}
|
||||
|
||||
type session struct {
|
||||
@ -197,14 +324,25 @@ type session struct {
|
||||
stderr io.ReadCloser
|
||||
}
|
||||
|
||||
func (s *session) run(t *testing.T, cmdString string) string {
|
||||
func (s *session) run(t *testing.T, cmdString string, shell bool) string {
|
||||
t.Helper()
|
||||
|
||||
if shell {
|
||||
_, err := s.stdin.Write([]byte(fmt.Sprintf("%s\n", cmdString)))
|
||||
if err != nil {
|
||||
t.Fatalf("unable to send command to shell: %s", err)
|
||||
}
|
||||
} else {
|
||||
err := s.Start(cmdString)
|
||||
if err != nil {
|
||||
t.Fatalf("unable to start command: %s", err)
|
||||
}
|
||||
}
|
||||
|
||||
return s.read()
|
||||
}
|
||||
|
||||
func (s *session) read() string {
|
||||
ch := make(chan []byte)
|
||||
go func() {
|
||||
for {
|
||||
@ -228,7 +366,7 @@ func (s *session) run(t *testing.T, cmdString string) string {
|
||||
select {
|
||||
case b := <-ch:
|
||||
_got = append(_got, b...)
|
||||
case <-time.After(25 * time.Millisecond):
|
||||
case <-time.After(1 * time.Second):
|
||||
break readLoop
|
||||
}
|
||||
}
|
||||
@ -236,12 +374,12 @@ func (s *session) run(t *testing.T, cmdString string) string {
|
||||
return string(_got)
|
||||
}
|
||||
|
||||
func testClient(t *testing.T) *ssh.Client {
|
||||
func testClient(t *testing.T, forceV1Behavior bool) *ssh.Client {
|
||||
t.Helper()
|
||||
|
||||
username := "testuser"
|
||||
srv := &server{
|
||||
lb: &testBackend{localUser: username},
|
||||
lb: &testBackend{localUser: username, forceV1Behavior: forceV1Behavior},
|
||||
logf: log.Printf,
|
||||
tailscaledPath: os.Getenv("TAILSCALED_PATH"),
|
||||
timeNow: time.Now,
|
||||
@ -271,8 +409,8 @@ func testClient(t *testing.T) *ssh.Client {
|
||||
return cl
|
||||
}
|
||||
|
||||
func testSession(t *testing.T) *session {
|
||||
cl := testClient(t)
|
||||
func testSession(t *testing.T, forceV1Behavior bool) *session {
|
||||
cl := testClient(t, forceV1Behavior)
|
||||
return testSessionFor(t, cl)
|
||||
}
|
||||
|
||||
@ -300,6 +438,7 @@ func testSessionFor(t *testing.T, cl *ssh.Client) *session {
|
||||
// testBackend implements ipnLocalBackend
|
||||
type testBackend struct {
|
||||
localUser string
|
||||
forceV1Behavior bool
|
||||
}
|
||||
|
||||
func (tb *testBackend) GetSSH_HostKeys() ([]gossh.Signer, error) {
|
||||
@ -339,16 +478,21 @@ func (tb *testBackend) ShouldRunSSH() bool {
|
||||
}
|
||||
|
||||
func (tb *testBackend) NetMap() *netmap.NetworkMap {
|
||||
capMap := make(set.Set[tailcfg.NodeCapability])
|
||||
if tb.forceV1Behavior {
|
||||
capMap[tailcfg.NodeAttrSSHBehaviorV1] = struct{}{}
|
||||
}
|
||||
return &netmap.NetworkMap{
|
||||
SSHPolicy: &tailcfg.SSHPolicy{
|
||||
Rules: []*tailcfg.SSHRule{
|
||||
&tailcfg.SSHRule{
|
||||
{
|
||||
Principals: []*tailcfg.SSHPrincipal{{Any: true}},
|
||||
Action: &tailcfg.SSHAction{Accept: true},
|
||||
SSHUsers: map[string]string{"*": tb.localUser},
|
||||
},
|
||||
},
|
||||
},
|
||||
AllCaps: capMap,
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
@ -1,18 +1,51 @@
|
||||
ARG BASE
|
||||
FROM ${BASE}
|
||||
|
||||
RUN echo "Install openssh, needed for scp."
|
||||
RUN apt-get update -y && apt-get install -y openssh-client
|
||||
|
||||
RUN groupadd -g 10000 groupone
|
||||
RUN groupadd -g 10001 grouptwo
|
||||
RUN useradd -g 10000 -G 10001 -u 10002 -m testuser
|
||||
COPY . .
|
||||
# Note - we do not create the user's home directory, pam_mkhomedir will do that
|
||||
# for us, and we want to test that PAM gets triggered by Tailscale SSH.
|
||||
RUN useradd -g 10000 -G 10001 -u 10002 testuser
|
||||
|
||||
# First run tests normally.
|
||||
RUN TAILSCALED_PATH=`pwd`tailscaled ./tailssh.test -test.run TestIntegration
|
||||
RUN echo "Set up pam_mkhomedir."
|
||||
RUN sed -i -e 's/Default: no/Default: yes/g' /usr/share/pam-configs/mkhomedir || echo "might not be ubuntu"
|
||||
RUN cat /usr/share/pam-configs/mkhomedir
|
||||
RUN pam-auth-update --enable mkhomedir
|
||||
|
||||
# Then remove the login command and make sure tests still pass.
|
||||
RUN rm `which login`
|
||||
RUN TAILSCALED_PATH=`pwd`tailscaled ./tailssh.test -test.run TestIntegration
|
||||
COPY tailscaled .
|
||||
COPY tailssh.test .
|
||||
|
||||
# Then run tests as non-root user testuser.
|
||||
RUN chmod 755 tailscaled
|
||||
|
||||
RUN echo "First run tests normally."
|
||||
RUN rm -Rf /home/testuser
|
||||
RUN TAILSCALED_PATH=`pwd`tailscaled ./tailssh.test -test.v -test.run TestIntegrationSFTP
|
||||
RUN rm -Rf /home/testuser
|
||||
RUN TAILSCALED_PATH=`pwd`tailscaled ./tailssh.test -test.v -test.run TestIntegrationSCP
|
||||
RUN rm -Rf /home/testuser
|
||||
RUN TAILSCALED_PATH=`pwd`tailscaled ./tailssh.test -test.v -test.run TestIntegrationSSH
|
||||
|
||||
RUN echo "Then run tests as non-root user testuser and make sure tests still pass."
|
||||
RUN chown testuser:groupone /tmp/tailscalessh.log
|
||||
RUN TAILSCALED_PATH=`pwd`tailscaled su -m testuser -c "./tailssh.test -test.run TestIntegration"
|
||||
RUN TAILSCALED_PATH=`pwd`tailscaled su -m testuser -c "./tailssh.test -test.v -test.run TestIntegration TestDoDropPrivileges"
|
||||
|
||||
RUN echo "Then remove the login command and make sure tests still pass."
|
||||
RUN chown root:root /tmp/tailscalessh.log
|
||||
RUN rm `which login`
|
||||
RUN rm -Rf /home/testuser
|
||||
RUN TAILSCALED_PATH=`pwd`tailscaled ./tailssh.test -test.v -test.run TestIntegrationSFTP
|
||||
RUN rm -Rf /home/testuser
|
||||
RUN TAILSCALED_PATH=`pwd`tailscaled ./tailssh.test -test.v -test.run TestIntegrationSCP
|
||||
RUN rm -Rf /home/testuser
|
||||
RUN TAILSCALED_PATH=`pwd`tailscaled ./tailssh.test -test.v -test.run TestIntegrationSSH
|
||||
|
||||
RUN echo "Then remove the su command and make sure tests still pass."
|
||||
RUN chown root:root /tmp/tailscalessh.log
|
||||
RUN rm `which su`
|
||||
RUN TAILSCALED_PATH=`pwd`tailscaled ./tailssh.test -test.v -test.run TestIntegration
|
||||
|
||||
RUN echo "Test doDropPrivileges"
|
||||
RUN TAILSCALED_PATH=`pwd`tailscaled ./tailssh.test -test.v -test.run TestDoDropPrivileges
|
||||
|
||||
@ -136,7 +136,8 @@
|
||||
// - 93: 2024-05-06: added support for stateful firewalling.
|
||||
// - 94: 2024-05-06: Client understands Node.IsJailed.
|
||||
// - 95: 2024-05-06: Client uses NodeAttrUserDialUseRoutes to change DNS dialing behavior.
|
||||
const CurrentCapabilityVersion CapabilityVersion = 95
|
||||
// - 96: 2024-05-29: Client understands NodeAttrSSHBehaviorV1
|
||||
const CurrentCapabilityVersion CapabilityVersion = 96
|
||||
|
||||
type StableID string
|
||||
|
||||
@ -2274,6 +2275,10 @@ type Oauth2Token struct {
|
||||
// depending on the destination address and the configured routes. When present, it also makes
|
||||
// the DNS forwarder use UserDial instead of SystemDial when dialing resolvers.
|
||||
NodeAttrUserDialUseRoutes NodeCapability = "user-dial-routes"
|
||||
|
||||
// NodeAttrSSHBehaviorV1 forces SSH to use the V1 behavior (no su, run SFTP in-process)
|
||||
// Added 2024-05-29 in Tailscale version 1.68.
|
||||
NodeAttrSSHBehaviorV1 NodeCapability = "ssh-behavior-v1"
|
||||
)
|
||||
|
||||
// SetDNSRequest is a request to add a DNS record.
|
||||
|
||||
Loading…
Reference in New Issue
Block a user