func (c *CloneParams) CloneFrozen() (int, error) {
pid := callClone(c)
// TODO: clone errors?
c.CommWriter.Close()
c.stdhandles.Close()
c.comm = make(chan CommStatus)
go commReader(c.CommReader, c.comm)
var status syscall.WaitStatus
for {
wpid, err := syscall.Wait4(pid, &status, 0, nil) // TODO: rusage
if err != nil {
return -1, os.NewSyscallError("Wait4", err)
}
if wpid == pid {
break
}
}
if status.Stopped() && status.StopSignal() == syscall.SIGTRAP {
return pid, nil
}
if status.Exited() {
co, ok := <-c.comm
if ok {
return -1, childError(co)
}
return -1, fmt.Errorf("DAFUQ")
}
err := syscall.Kill(pid, syscall.SIGKILL)
if err != nil {
return -1, os.NewSyscallError("Kill", err)
}
return -1, fmt.Errorf("traps, signals, dafuq is this")
}
// waitStatusToStateUpdate converts syscall.WaitStatus to a StateUpdate.
func waitStatusToStateUpdate(ws syscall.WaitStatus) *stateUpdate {
switch {
case ws.Exited():
es := ws.ExitStatus()
if es == 0 {
return newExitedStateUpdate(ok)
}
return newExitedStateUpdate(newFailure(fmt.Sprint(es)))
case ws.Signaled():
msg := fmt.Sprintf("signaled %v", ws.Signal())
if ws.CoreDump() {
msg += " (core dumped)"
}
return newUnexitedStateUpdate(msg)
case ws.Stopped():
msg := fmt.Sprintf("stopped %v", ws.StopSignal())
trap := ws.TrapCause()
if trap != -1 {
msg += fmt.Sprintf(" (trapped %v)", trap)
}
return newUnexitedStateUpdate(msg)
case ws.Continued():
return newUnexitedStateUpdate("continued")
default:
return newUnexitedStateUpdate(fmt.Sprint("unknown status", ws))
}
}
func printStatus(ws syscall.WaitStatus) string {
switch {
case ws.Exited():
es := ws.ExitStatus()
if es == 0 {
return ""
}
return fmt.Sprintf("exited %v", es)
case ws.Signaled():
msg := fmt.Sprintf("signaled %v", ws.Signal())
if ws.CoreDump() {
msg += " (core dumped)"
}
return msg
case ws.Stopped():
msg := fmt.Sprintf("stopped %v", ws.StopSignal())
trap := ws.TrapCause()
if trap != -1 {
msg += fmt.Sprintf(" (trapped %v)", trap)
}
return msg
case ws.Continued():
return "continued"
default:
return fmt.Sprintf("unknown status %v", ws)
}
}
func handleSigchld(mpid int) *resultPack {
for {
var status syscall.WaitStatus
var spid int
var err error
spid, err = syscall.Wait4(-mpid, &status, syscall.WNOHANG|syscall.WALL, nil)
if err != nil {
poePanic(err, "wait4 failed")
} else if spid == 0 {
return nil
}
if spid == mpid && status.Exited() {
return &resultPack{POE_SUCCESS, status.ExitStatus(), ""}
} else if spid == mpid && status.Signaled() {
return &resultPack{POE_SIGNALED, -1, fmt.Sprintf("Program terminated with signal %d (%s)", int(status.Signal()), status.Signal().String())}
} else if status.Stopped() {
e := status >> 16 & 0xff
switch e {
case PTRACE_EVENT_SECCOMP:
if res := handleSyscall(spid); res != nil {
return res
}
case syscall.PTRACE_EVENT_CLONE, syscall.PTRACE_EVENT_FORK, syscall.PTRACE_EVENT_VFORK:
syscall.PtraceCont(spid, 0)
default:
syscall.PtraceCont(spid, int(status.StopSignal()))
}
}
}
}
// waitStatusToError converts syscall.WaitStatus to an Error.
func waitStatusToError(ws syscall.WaitStatus) error {
switch {
case ws.Exited():
es := ws.ExitStatus()
if es == 0 {
return nil
}
return errors.New(fmt.Sprint(es))
case ws.Signaled():
msg := fmt.Sprintf("signaled %v", ws.Signal())
if ws.CoreDump() {
msg += " (core dumped)"
}
return errors.New(msg)
case ws.Stopped():
msg := fmt.Sprintf("stopped %v", ws.StopSignal())
trap := ws.TrapCause()
if trap != -1 {
msg += fmt.Sprintf(" (trapped %v)", trap)
}
return errors.New(msg)
/*
case ws.Continued():
return newUnexitedStateUpdate("continued")
*/
default:
return fmt.Errorf("unknown WaitStatus", ws)
}
}
func ChildWaitingFunc(pid int, sig chan *ChildWaitData) {
var status syscall.WaitStatus
var rusage syscall.Rusage
result := &ChildWaitData{}
for {
wpid, err := syscall.Wait4(pid, &status, syscall.WUNTRACED|syscall.WCONTINUED, &rusage)
if wpid != pid {
continue
}
if status.Exited() {
result.ExitCode = uint32(status.ExitStatus())
break
}
if status.Stopped() {
result.SuccessCode |= EF_STOPPED
result.StopSignal = uint32(status.StopSignal())
syscall.Kill(pid, syscall.SIGKILL)
}
if status.Signaled() {
result.SuccessCode |= EF_KILLED_BY_OTHER
result.KillSignal = uint32(status.Signal())
break
}
if err != nil {
break
}
}
result.RusageCpuUser = time.Nanosecond * time.Duration(rusage.Utime.Nano())
result.RusageCpuKernel = time.Nanosecond * time.Duration(rusage.Stime.Nano())
sig <- result
close(sig)
}
func wait_for_syscall(pid int) (exited bool, err error) {
var waitStatus syscall.WaitStatus
for {
// Entering a syscall
if err = syscall.PtraceSyscall(pid, 0); err != nil {
return
}
if _, err = syscall.Wait4(pid, &waitStatus, 0, nil); err != nil {
return
}
// Is it for us ?
if waitStatus.Stopped() && waitStatus.StopSignal()&0x80 == 0x80 {
return
}
if waitStatus.Exited() {
exited = true
return
}
}
}
func (t *PTracer) handleStopped(pid int, status syscall.WaitStatus) {
signal := syscall.Signal(0)
target, err := t.thread(pid)
if err != nil {
log.Printf("thread failed: %v", err)
return
}
if !target.attached {
target.attached = true
err = syscall.PtraceSetOptions(pid, ptraceOptions)
if err != nil {
log.Printf("SetOptions failed, pid=%d, err=%v", pid, err)
return
}
} else if status.Stopped() && status.StopSignal() == syscall.SIGTRAP|ptraceTracesysgoodBit {
// pid entered Syscall-enter-stop or syscall-exit-stop
target.syscallStopped()
} else if status.Stopped() && status.StopSignal() == syscall.SIGTRAP {
// pid entered PTRACE_EVENT stop
switch status.TrapCause() {
case syscall.PTRACE_EVENT_CLONE:
err := target.handleClone(pid)
if err != nil {
log.Printf("clone failed: %v", err)
return
}
default:
log.Printf("Unknown PTRACE_EVENT %d for pid %d", status.TrapCause(), pid)
}
} else if status.Exited() || status.Signaled() {
// "tracer can safely assume pid will exit"
t.threadExited(target)
return
} else if status.Stopped() {
// tracee received a non-trace related signal
signal = status.StopSignal()
if signal == syscall.SIGSTOP && target.process.detaching {
t.detachThread(target)
return
}
} else {
// unknown stop - shouldn't happen!
log.Printf("Pid %d random stop with status %x", pid, status)
}
// Restart stopped caller in syscall trap mode.
// log.Printf("Restarting pid %d with signal %d", pid, int(signal))
err = syscall.PtraceSyscall(pid, int(signal))
if err != nil {
log.Printf("PtraceSyscall failed, pid=%d, err=%v", pid, err)
}
}
func Tracer() {
var train = false
var cmd string
var cmdArgs []string
var p *oz.Profile
var noprofile = flag.Bool("train", false, "Training mode")
var debug = flag.Bool("debug", false, "Debug")
var appendpolicy = flag.Bool("append", false, "Append to existing policy if exists")
var trainingoutput = flag.String("output", "", "Training policy output file")
flag.Parse()
var args = flag.Args()
if *noprofile == true {
train = true
// TODO: remove hardcoded path and read prefix from /etc/oz.conf
cmd = "/usr/bin/oz-seccomp"
cmdArgs = append([]string{"-mode=train"}, args...)
} else {
p = new(oz.Profile)
if err := json.NewDecoder(os.Stdin).Decode(&p); err != nil {
log.Error("unable to decode profile data: %v", err)
os.Exit(1)
}
if p.Seccomp.Mode == oz.PROFILE_SECCOMP_TRAIN {
train = true
}
*debug = p.Seccomp.Debug
cmd = args[0]
cmdArgs = args[1:]
}
var cpid = 0
done := false
log.Info("Tracer running command (%v) arguments (%v)\n", cmd, cmdArgs)
c := exec.Command(cmd)
c.SysProcAttr = &syscall.SysProcAttr{Ptrace: true}
c.Env = os.Environ()
c.Args = append(c.Args, cmdArgs...)
if *noprofile == false {
pi, err := c.StdinPipe()
if err != nil {
fmt.Errorf("error creating stdin pipe for tracer process: %v", err)
os.Exit(1)
}
jdata, err := json.Marshal(p)
if err != nil {
fmt.Errorf("Unable to marshal seccomp state: %+v", err)
os.Exit(1)
}
io.Copy(pi, bytes.NewBuffer(jdata))
pi.Close()
}
children := make(map[int]bool)
renderFunctions := getRenderingFunctions()
trainingset := make(map[int]bool)
trainingargs := make(map[int]map[int][]uint)
if err := c.Start(); err == nil {
cpid = c.Process.Pid
children[c.Process.Pid] = true
var s syscall.WaitStatus
pid, err := syscall.Wait4(-1, &s, syscall.WALL, nil)
children[pid] = true
if err != nil {
log.Error("Error (wait4) err:%v pid:%i", err, pid)
}
log.Info("Tracing child pid: %v\n", pid)
for done == false {
pflags := unix.PTRACE_O_TRACESECCOMP
pflags |= unix.PTRACE_O_TRACEFORK
pflags |= unix.PTRACE_O_TRACEVFORK
pflags |= unix.PTRACE_O_TRACECLONE
pflags |= C.PTRACE_O_EXITKILL
syscall.PtraceSetOptions(pid, pflags)
syscall.PtraceCont(pid, 0)
pid, err = syscall.Wait4(-1, &s, syscall.WALL, nil)
if err != nil {
log.Error("Error (wait4) err:%v pid:%i children:%v\n", err, pid, children)
done = true
continue
}
children[pid] = true
if s.Exited() == true {
delete(children, pid)
log.Info("Child pid %v finished.\n", pid)
if len(children) == 0 {
done = true
}
continue
}
if s.Signaled() == true {
log.Error("Pid signaled, pid: %v signal: %v", pid, s)
delete(children, pid)
continue
}
switch uint32(s) >> 8 {
case uint32(unix.SIGTRAP) | (unix.PTRACE_EVENT_SECCOMP << 8):
var regs syscall.PtraceRegs
err = syscall.PtraceGetRegs(pid, ®s)
if err != nil {
log.Error("Error (ptrace): %v", err)
}
systemcall, err := syscallByNum(getSyscallNumber(regs))
if err != nil {
log.Error("Error: %v", err)
continue
}
/* Render the system call invocation */
r := getSyscallRegisterArgs(regs)
call := ""
if train == true {
trainingset[getSyscallNumber(regs)] = true
if systemcall.captureArgs != nil {
for c, i := range systemcall.captureArgs {
if i == 1 {
if trainingargs[getSyscallNumber(regs)] == nil {
trainingargs[getSyscallNumber(regs)] = make(map[int][]uint)
}
if contains(trainingargs[getSyscallNumber(regs)][c], uint(r[c])) == false {
trainingargs[getSyscallNumber(regs)][c] = append(trainingargs[getSyscallNumber(regs)][c], uint(r[c]))
}
}
}
}
}
if f, ok := renderFunctions[getSyscallNumber(regs)]; ok {
call, err = f(pid, r)
if err != nil {
log.Info("%v", err)
continue
}
if *debug == true {
call += "\n " + renderSyscallBasic(pid, systemcall, regs)
}
} else {
call = renderSyscallBasic(pid, systemcall, regs)
}
log.Info("seccomp hit on sandbox pid %v (%v) syscall %v (%v):\n %s", pid, getProcessCmdLine(pid), systemcall.name, systemcall.num, call)
continue
case uint32(unix.SIGTRAP) | (unix.PTRACE_EVENT_EXIT << 8):
if *debug == true {
log.Error("Ptrace exit event detected pid %v (%s)", pid, getProcessCmdLine(pid))
}
delete(children, pid)
continue
case uint32(unix.SIGTRAP) | (unix.PTRACE_EVENT_CLONE << 8):
newpid, err := syscall.PtraceGetEventMsg(pid)
if err != nil {
log.Error("PTrace event message retrieval failed: %v", err)
}
children[int(newpid)] = true
if *debug == true {
log.Error("Ptrace clone event detected pid %v (%s)", pid, getProcessCmdLine(pid))
}
continue
case uint32(unix.SIGTRAP) | (unix.PTRACE_EVENT_FORK << 8):
if *debug == true {
log.Error("PTrace fork event detected pid %v (%s)", pid, getProcessCmdLine(pid))
}
newpid, err := syscall.PtraceGetEventMsg(pid)
if err != nil {
log.Error("PTrace event message retrieval failed: %v", err)
}
children[int(newpid)] = true
continue
case uint32(unix.SIGTRAP) | (unix.PTRACE_EVENT_VFORK << 8):
if *debug == true {
log.Error("Ptrace vfork event detected pid %v (%s)", pid, getProcessCmdLine(pid))
}
newpid, err := syscall.PtraceGetEventMsg(pid)
if err != nil {
log.Error("PTrace event message retrieval failed: %v", err)
}
children[int(newpid)] = true
continue
case uint32(unix.SIGTRAP) | (unix.PTRACE_EVENT_VFORK_DONE << 8):
if *debug == true {
log.Error("Ptrace vfork done event detected pid %v (%s)", pid, getProcessCmdLine(pid))
}
newpid, err := syscall.PtraceGetEventMsg(pid)
if err != nil {
log.Error("PTrace event message retrieval failed: %v", err)
}
children[int(newpid)] = true
continue
case uint32(unix.SIGTRAP) | (unix.PTRACE_EVENT_EXEC << 8):
if *debug == true {
log.Error("Ptrace exec event detected pid %v (%s)", pid, getProcessCmdLine(pid))
}
continue
case uint32(unix.SIGTRAP) | (unix.PTRACE_EVENT_STOP << 8):
if *debug == true {
log.Error("Ptrace stop event detected pid %v (%s)", pid, getProcessCmdLine(pid))
}
continue
case uint32(unix.SIGTRAP):
if *debug == true {
log.Error("SIGTRAP detected in pid %v (%s)", pid, getProcessCmdLine(pid))
}
continue
case uint32(unix.SIGCHLD):
if *debug == true {
log.Error("SIGCHLD detected pid %v (%s)", pid, getProcessCmdLine(pid))
}
continue
case uint32(unix.SIGSTOP):
if *debug == true {
log.Error("SIGSTOP detected pid %v (%s)", pid, getProcessCmdLine(pid))
}
continue
case uint32(unix.SIGSEGV):
if *debug == true {
log.Error("SIGSEGV detected pid %v (%s)", pid, getProcessCmdLine(pid))
}
err = syscall.Kill(pid, 9)
if err != nil {
log.Error("kill: %v", err)
os.Exit(1)
}
delete(children, pid)
continue
default:
y := s.StopSignal()
if *debug == true {
log.Error("Child stopped for unknown reasons pid %v status %v signal %i (%s)", pid, s, y, getProcessCmdLine(pid))
}
continue
}
}
if train == true {
var u *user.User
var e error
u, e = user.Current()
var resolvedpath = ""
if e != nil {
log.Error("user.Current(): %v", e)
}
if *trainingoutput != "" {
resolvedpath = *trainingoutput
} else {
if *noprofile == false {
resolvedpath, e = fs.ResolvePathNoGlob(p.Seccomp.TrainOutput, u)
if e != nil {
log.Error("resolveVars(): %v", e)
}
} else {
s := fmt.Sprintf("${HOME}/%s-%d.seccomp", fname(os.Args[2]), cpid)
resolvedpath, e = fs.ResolvePathNoGlob(s, u)
}
}
policyout := "execve:1\n"
for call := range trainingset {
done := false
for c := range trainingargs {
if c == call {
for a, v := range trainingargs[c] {
sc, _ := syscallByNum(call)
policyout += fmt.Sprintf("%s:%s\n", sc.name, genArgs(uint(a), (v)))
done = true
}
}
}
if done == false {
sc, _ := syscallByNum(call)
policyout += fmt.Sprintf("%s:1\n", sc.name)
}
}
if *appendpolicy == true {
log.Error("Not yet implemented.")
}
f, err := os.OpenFile(resolvedpath, os.O_CREATE|os.O_RDWR, 0600)
if err == nil {
_, err := f.WriteString(policyout)
if err != nil {
log.Error("Error writing policy file: %v", err)
}
err = f.Close()
if err != nil {
log.Error("Error closing policy file: %v", err)
}
} else {
log.Error("Error opening policy file \"%s\": %v", resolvedpath, err)
}
}
}
}
func Tracer() {
p := new(oz.Profile)
if err := json.NewDecoder(os.Stdin).Decode(&p); err != nil {
log.Error("unable to decode profile data: %v", err)
os.Exit(1)
}
var proc_attr syscall.ProcAttr
var sys_attr syscall.SysProcAttr
sys_attr.Ptrace = true
done := false
proc_attr.Sys = &sys_attr
cmd := os.Args[1]
cmdArgs := os.Args[2:]
log.Info("Tracer running command (%v) arguments (%v)\n", cmd, cmdArgs)
c := exec.Command(cmd)
c.SysProcAttr = &syscall.SysProcAttr{Ptrace: true}
c.Env = os.Environ()
c.Args = append(c.Args, cmdArgs...)
pi, err := c.StdinPipe()
if err != nil {
fmt.Errorf("error creating stdin pipe for tracer process: %v", err)
os.Exit(1)
}
jdata, err := json.Marshal(p)
if err != nil {
fmt.Errorf("Unable to marshal seccomp state: %+v", err)
os.Exit(1)
}
io.Copy(pi, bytes.NewBuffer(jdata))
log.Info(string(jdata))
pi.Close()
children := make(map[int]bool)
renderFunctions := getRenderingFunctions()
if err := c.Start(); err == nil {
children[c.Process.Pid] = true
var s syscall.WaitStatus
pid, err := syscall.Wait4(-1, &s, syscall.WALL, nil)
children[pid] = true
if err != nil {
log.Error("Error (wait4) here first: %v %i", err, pid)
}
log.Info("Tracing child pid: %v\n", pid)
for done == false {
syscall.PtraceSetOptions(pid, unix.PTRACE_O_TRACESECCOMP|unix.PTRACE_O_TRACEFORK|unix.PTRACE_O_TRACEVFORK|unix.PTRACE_O_TRACECLONE)
syscall.PtraceCont(pid, 0)
pid, err = syscall.Wait4(-1, &s, syscall.WALL, nil)
if err != nil {
log.Error("Error (wait4) here: %v %i %v\n", err, pid, children)
if len(children) == 0 {
done = true
}
continue
}
children[pid] = true
if s.Exited() == true {
delete(children, pid)
log.Info("Child pid %v finished.\n", pid)
if len(children) == 0 {
done = true
}
continue
}
if s.Signaled() == true {
log.Error("Other pid signalled %v %v", pid, s)
delete(children, pid)
continue
}
switch uint32(s) >> 8 {
case uint32(unix.SIGTRAP) | (unix.PTRACE_EVENT_SECCOMP << 8):
if err != nil {
log.Error("Error (ptrace): %v", err)
continue
}
var regs syscall.PtraceRegs
err = syscall.PtraceGetRegs(pid, ®s)
if err != nil {
log.Error("Error (ptrace): %v", err)
}
systemcall, err := syscallByNum(getSyscallNumber(regs))
if err != nil {
log.Error("Error: %v", err)
continue
}
/* Render the system call invocation */
r := getSyscallRegisterArgs(regs)
call := ""
if f, ok := renderFunctions[getSyscallNumber(regs)]; ok {
call, err = f(pid, r)
if err != nil {
log.Info("%v", err)
continue
}
} else {
call = renderSyscallBasic(pid, systemcall, regs)
}
log.Info("==============================================\nseccomp hit on sandbox pid %v (%v) syscall %v (%v):\n\n%s\nI ==============================================\n\n", pid, getProcessCmdLine(pid), systemcall.name, systemcall.num, call)
continue
case uint32(unix.SIGTRAP) | (unix.PTRACE_EVENT_EXIT << 8):
log.Error("Ptrace exit event detected pid %v (%s)", pid, getProcessCmdLine(pid))
case uint32(unix.SIGTRAP) | (unix.PTRACE_EVENT_CLONE << 8):
log.Error("Ptrace clone event detected pid %v (%s)", pid, getProcessCmdLine(pid))
continue
case uint32(unix.SIGTRAP) | (unix.PTRACE_EVENT_FORK << 8):
log.Error("PTrace fork event detected pid %v (%s)", pid, getProcessCmdLine(pid))
continue
case uint32(unix.SIGTRAP) | (unix.PTRACE_EVENT_VFORK << 8):
log.Error("Ptrace vfork event detected pid %v (%s)", pid, getProcessCmdLine(pid))
continue
case uint32(unix.SIGTRAP) | (unix.PTRACE_EVENT_VFORK_DONE << 8):
log.Error("Ptrace vfork done event detected pid %v (%s)", pid, getProcessCmdLine(pid))
continue
case uint32(unix.SIGTRAP) | (unix.PTRACE_EVENT_EXEC << 8):
log.Error("Ptrace exec event detected pid %v (%s)", pid, getProcessCmdLine(pid))
continue
case uint32(unix.SIGTRAP) | (unix.PTRACE_EVENT_STOP << 8):
log.Error("Ptrace stop event detected pid %v (%s)", pid, getProcessCmdLine(pid))
continue
case uint32(unix.SIGTRAP):
log.Error("SIGTRAP detected in pid %v (%s)", pid, getProcessCmdLine(pid))
continue
case uint32(unix.SIGCHLD):
log.Error("SIGCHLD detected pid %v (%s)", pid, getProcessCmdLine(pid))
continue
case uint32(unix.SIGSTOP):
log.Error("SIGSTOP detected pid %v (%s)", pid, getProcessCmdLine(pid))
continue
default:
y := s.StopSignal()
log.Error("Child stopped for unknown reasons pid %v status %v signal %i (%s)", pid, s, y, getProcessCmdLine(pid))
continue
}
}
}
}
