func main() {
defer func() {
if r := recover(); r != nil {
log.Errorf("run time panic: %s : %s", r, debug.Stack())
}
reboot()
}()
src, err := extraconfig.GuestInfoSourceWithPrefix("init")
if err != nil {
log.Error(err)
return
}
extraconfig.Decode(src, &config)
debugLevel = config.Diagnostics.DebugLevel
if debugLevel > 2 {
enableShell()
}
setLogLevels()
logFile, err := os.OpenFile("/dev/ttyS1", os.O_WRONLY|os.O_SYNC, 0644)
if err != nil {
log.Errorf("Could not pipe stderr to serial for debugging info. Some debug info may be lost! Error reported was %s", err)
}
err = syscall.Dup3(int(logFile.Fd()), int(os.Stderr.Fd()), 0)
if err != nil {
log.Errorf("Could not pipe logfile to standard error due to error %s", err)
}
_, err = os.Stderr.WriteString("all stderr redirected to debug log")
if err != nil {
log.Errorf("Could not write to Stderr due to error %s", err)
}
sink, err := extraconfig.GuestInfoSinkWithPrefix("init")
if err != nil {
log.Error(err)
return
}
// create the tether
tthr = tether.New(src, sink, &operations{})
// register the toolbox extension and configure for appliance
toolbox := configureToolbox(tether.NewToolbox())
toolbox.PrimaryIP = externalIP
tthr.Register("Toolbox", toolbox)
err = tthr.Start()
if err != nil {
log.Error(err)
return
}
log.Info("Clean exit from init")
}
/*
* This is called by lxd when called as "lxd forkstart <container>"
* 'forkstart' is used instead of just 'start' in the hopes that people
* do not accidentally type 'lxd start' instead of 'lxc start'
*
* We expect to read the lxcconfig over fd 3.
*/
func startContainer(args []string) error {
if len(args) != 4 {
return fmt.Errorf("Bad arguments: %q", args)
}
name := args[1]
lxcpath := args[2]
configPath := args[3]
c, err := lxc.NewContainer(name, lxcpath)
if err != nil {
return fmt.Errorf("Error initializing container for start: %q", err)
}
err = c.LoadConfigFile(configPath)
if err != nil {
return fmt.Errorf("Error opening startup config file: %q", err)
}
/* due to https://github.com/golang/go/issues/13155 and the
* CollectOutput call we make for the forkstart process, we need to
* close our stdin/stdout/stderr here. Collecting some of the logs is
* better than collecting no logs, though.
*/
os.Stdin.Close()
os.Stderr.Close()
os.Stdout.Close()
// Redirect stdout and stderr to a log file
logPath := shared.LogPath(name, "forkstart.log")
if shared.PathExists(logPath) {
os.Remove(logPath)
}
logFile, err := os.OpenFile(logPath, os.O_WRONLY|os.O_CREATE|os.O_SYNC, 0644)
if err == nil {
syscall.Dup3(int(logFile.Fd()), 1, 0)
syscall.Dup3(int(logFile.Fd()), 2, 0)
}
// Move the config so we can inspect it on failure
shared.FileMove(configPath, shared.LogPath(name, "lxc.conf"))
return c.Start()
}
func setupLogging(config *Config) error {
if config.LogFile == "" {
return nil
}
if err := createDirs(path.Dir(config.LogFile)); err != nil {
return err
}
output, err := os.Create(config.LogFile)
if err != nil {
return err
}
syscall.Dup3(int(output.Fd()), int(os.Stdout.Fd()), 0)
syscall.Dup3(int(output.Fd()), int(os.Stderr.Fd()), 0)
return nil
}
func setupLogging(config *Config) error {
if config.LogFile == "" {
return nil
}
if err := createDirs(path.Dir(config.LogFile)); err != nil {
return err
}
output, err := os.OpenFile(config.LogFile, os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
if err != nil {
return err
}
syscall.Dup3(int(output.Fd()), int(os.Stdout.Fd()), 0)
syscall.Dup3(int(output.Fd()), int(os.Stderr.Fd()), 0)
return nil
}
// dupStdio opens the slavePath for the console and dups the fds to the current
// processes stdio, fd 0,1,2.
func (c *linuxConsole) dupStdio() error {
slave, err := c.open(syscall.O_RDWR)
if err != nil {
return err
}
fd := int(slave.Fd())
for _, i := range []int{0, 1, 2} {
if err := syscall.Dup3(fd, i, 0); err != nil {
return err
}
}
return nil
}
// If stdin, stdout, and/or stderr are pointing to `/dev/null` in the parent's rootfs
// this method will make them point to `/dev/null` in this container's rootfs. This
// needs to be called after we chroot/pivot into the container's rootfs so that any
// symlinks are resolved locally.
func reOpenDevNull(rootfs string) error {
var stat, devNullStat syscall.Stat_t
file, err := os.Open("/dev/null")
if err != nil {
return fmt.Errorf("Failed to open /dev/null - %s", err)
}
defer file.Close()
if err := syscall.Fstat(int(file.Fd()), &devNullStat); err != nil {
return err
}
for fd := 0; fd < 3; fd++ {
if err := syscall.Fstat(fd, &stat); err != nil {
return err
}
if stat.Rdev == devNullStat.Rdev {
// Close and re-open the fd.
if err := syscall.Dup3(int(file.Fd()), fd, 0); err != nil {
return err
}
}
}
return nil
}
func main() {
defer func() {
if r := recover(); r != nil {
log.Errorf("run time panic: %s : %s", r, debug.Stack())
}
halt()
}()
logFile, err := os.OpenFile("/dev/ttyS1", os.O_WRONLY|os.O_SYNC, 0644)
if err != nil {
log.Errorf("Could not open serial port for debugging info. Some debug info may be lost! Error reported was %s", err)
}
if err = syscall.Dup3(int(logFile.Fd()), int(os.Stderr.Fd()), 0); err != nil {
log.Errorf("Could not pipe logfile to standard error due to error %s", err)
}
if _, err = os.Stderr.WriteString("all stderr redirected to debug log"); err != nil {
log.Errorf("Could not write to Stderr due to error %s", err)
}
// where to look for the various devices and files related to tether
pathPrefix = "/.tether"
if strings.HasSuffix(os.Args[0], "-debug") {
extraconfig.DecodeLogLevel = log.DebugLevel
extraconfig.EncodeLogLevel = log.DebugLevel
}
// use the same logger for trace and other logging
trace.Logger = log.StandardLogger()
log.SetLevel(log.DebugLevel)
// Initiliaze logger with default TextFormatter
log.SetFormatter(&log.TextFormatter{DisableColors: true, FullTimestamp: true})
// TODO: hard code executor initialization status reporting via guestinfo here
err = createDevices()
if err != nil {
log.Error(err)
// return gives us good behaviour in the case of "-debug" binary
return
}
sshserver := NewAttachServerSSH()
src, err := extraconfig.GuestInfoSource()
if err != nil {
log.Error(err)
return
}
sink, err := extraconfig.GuestInfoSink()
if err != nil {
log.Error(err)
return
}
// create the tether
tthr = tether.New(src, sink, &operations{})
// register the attach extension
tthr.Register("Attach", sshserver)
// register the toolbox extension
tthr.Register("Toolbox", tether.NewToolbox().InContainer())
err = tthr.Start()
if err != nil {
log.Error(err)
return
}
log.Info("Clean exit from tether")
}
/*
* This is called by lxd when called as "lxd forkexec <container>"
*/
func execContainer(args []string) (int, error) {
if len(args) < 6 {
return -1, fmt.Errorf("Bad arguments: %q", args)
}
wait := true
if args[1] == "nowait" {
wait = false
}
name := args[2]
lxcpath := args[3]
configPath := args[4]
c, err := lxc.NewContainer(name, lxcpath)
if err != nil {
return -1, fmt.Errorf("Error initializing container for start: %q", err)
}
err = c.LoadConfigFile(configPath)
if err != nil {
return -1, fmt.Errorf("Error opening startup config file: %q", err)
}
syscall.Dup3(int(os.Stdin.Fd()), 200, 0)
syscall.Dup3(int(os.Stdout.Fd()), 201, 0)
syscall.Dup3(int(os.Stderr.Fd()), 202, 0)
syscall.Close(int(os.Stdin.Fd()))
syscall.Close(int(os.Stdout.Fd()))
syscall.Close(int(os.Stderr.Fd()))
opts := lxc.DefaultAttachOptions
opts.ClearEnv = true
opts.StdinFd = 200
opts.StdoutFd = 201
opts.StderrFd = 202
logPath := shared.LogPath(name, "forkexec.log")
if shared.PathExists(logPath) {
os.Remove(logPath)
}
logFile, err := os.OpenFile(logPath, os.O_WRONLY|os.O_CREATE|os.O_SYNC, 0644)
if err == nil {
syscall.Dup3(int(logFile.Fd()), 1, 0)
syscall.Dup3(int(logFile.Fd()), 2, 0)
}
env := []string{}
cmd := []string{}
section := ""
for _, arg := range args[5:len(args)] {
// The "cmd" section must come last as it may contain a --
if arg == "--" && section != "cmd" {
section = ""
continue
}
if section == "" {
section = arg
continue
}
if section == "env" {
fields := strings.SplitN(arg, "=", 2)
if len(fields) == 2 && fields[0] == "HOME" {
opts.Cwd = fields[1]
}
env = append(env, arg)
} else if section == "cmd" {
cmd = append(cmd, arg)
} else {
return -1, fmt.Errorf("Invalid exec section: %s", section)
}
}
opts.Env = env
var status int
if wait {
status, err = c.RunCommandStatus(cmd, opts)
if err != nil {
return -1, fmt.Errorf("Failed running command and waiting for it to exit: %q", err)
}
} else {
status, err = c.RunCommandNoWait(cmd, opts)
if err != nil {
return -1, fmt.Errorf("Failed running command: %q", err)
}
// Send the PID of the executing process.
w := os.NewFile(uintptr(3), "attachedPid")
defer w.Close()
err = json.NewEncoder(w).Encode(status)
if err != nil {
return -1, fmt.Errorf("Failed sending PID of executing command: %q", err)
}
proc, err := os.FindProcess(status)
if err != nil {
return -1, fmt.Errorf("Failed finding process: %q", err)
}
procState, err := proc.Wait()
if err != nil {
return -1, fmt.Errorf("Failed waiting on process %d: %q", status, err)
}
if procState.Success() {
return 0, nil
}
status, ok := procState.Sys().(syscall.WaitStatus)
if ok {
if status.Exited() {
return status.ExitStatus(), nil
}
// Backwards compatible behavior. Report success when we exited
// due to a signal. Otherwise this may break Jenkins, e.g. when
// lxc exec foo reboot receives SIGTERM and status.Exitstats()
// would report -1.
if status.Signaled() {
return 0, nil
}
}
return -1, fmt.Errorf("Command failed")
}
return status >> 8, nil
}
func dup2(oldfd, newfd int) error {
return syscall.Dup3(oldfd, newfd, 0)
}
// Always use dup3 on Linux because dup2 is not available on arm64.
func dup2(sourceFD, targetFD int) error {
return syscall.Dup3(sourceFD, targetFD, 0)
}
/*
* This is called by lxd when called as "lxd forkexec <container>"
*/
func execContainer(args []string) (int, error) {
if len(args) < 6 {
return -1, fmt.Errorf("Bad arguments: %q", args)
}
name := args[1]
lxcpath := args[2]
configPath := args[3]
c, err := lxc.NewContainer(name, lxcpath)
if err != nil {
return -1, fmt.Errorf("Error initializing container for start: %q", err)
}
err = c.LoadConfigFile(configPath)
if err != nil {
return -1, fmt.Errorf("Error opening startup config file: %q", err)
}
syscall.Dup3(int(os.Stdin.Fd()), 200, 0)
syscall.Dup3(int(os.Stdout.Fd()), 201, 0)
syscall.Dup3(int(os.Stderr.Fd()), 202, 0)
syscall.Close(int(os.Stdin.Fd()))
syscall.Close(int(os.Stdout.Fd()))
syscall.Close(int(os.Stderr.Fd()))
opts := lxc.DefaultAttachOptions
opts.ClearEnv = true
opts.StdinFd = 200
opts.StdoutFd = 201
opts.StderrFd = 202
logPath := shared.LogPath(name, "forkexec.log")
if shared.PathExists(logPath) {
os.Remove(logPath)
}
logFile, err := os.OpenFile(logPath, os.O_WRONLY|os.O_CREATE|os.O_SYNC, 0644)
if err == nil {
syscall.Dup3(int(logFile.Fd()), 1, 0)
syscall.Dup3(int(logFile.Fd()), 2, 0)
}
env := []string{}
cmd := []string{}
section := ""
for _, arg := range args[5:len(args)] {
// The "cmd" section must come last as it may contain a --
if arg == "--" && section != "cmd" {
section = ""
continue
}
if section == "" {
section = arg
continue
}
if section == "env" {
fields := strings.SplitN(arg, "=", 2)
if len(fields) == 2 && fields[0] == "HOME" {
opts.Cwd = fields[1]
}
env = append(env, arg)
} else if section == "cmd" {
cmd = append(cmd, arg)
} else {
return -1, fmt.Errorf("Invalid exec section: %s", section)
}
}
opts.Env = env
status, err := c.RunCommandStatus(cmd, opts)
if err != nil {
return -1, fmt.Errorf("Failed running command: %q", err)
}
return status >> 8, nil
}
// linux_arm64 doesn't have syscall.Dup2 which ginkgo uses, so
// use the nearly identical syscall.Dup3 instead
func syscallDup(oldfd int, newfd int) (err error) {
return syscall.Dup3(oldfd, newfd, 0)
}
