1 //===-- ProcessKDP.cpp ------------------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include <errno.h>
11 #include <stdlib.h>
12 
13 #include <mutex>
14 
15 #include "lldb/Core/Debugger.h"
16 #include "lldb/Core/Module.h"
17 #include "lldb/Core/ModuleSpec.h"
18 #include "lldb/Core/PluginManager.h"
19 #include "lldb/Host/ConnectionFileDescriptor.h"
20 #include "lldb/Host/Host.h"
21 #include "lldb/Host/Symbols.h"
22 #include "lldb/Host/ThreadLauncher.h"
23 #include "lldb/Host/common/TCPSocket.h"
24 #include "lldb/Interpreter/CommandInterpreter.h"
25 #include "lldb/Interpreter/CommandObject.h"
26 #include "lldb/Interpreter/CommandObjectMultiword.h"
27 #include "lldb/Interpreter/CommandReturnObject.h"
28 #include "lldb/Interpreter/OptionGroupString.h"
29 #include "lldb/Interpreter/OptionGroupUInt64.h"
30 #include "lldb/Interpreter/OptionValueProperties.h"
31 #include "lldb/Symbol/ObjectFile.h"
32 #include "lldb/Target/RegisterContext.h"
33 #include "lldb/Target/Target.h"
34 #include "lldb/Target/Thread.h"
35 #include "lldb/Utility/State.h"
36 #include "lldb/Utility/StringExtractor.h"
37 #include "lldb/Utility/UUID.h"
38 
39 #include "llvm/Support/Threading.h"
40 
41 #define USEC_PER_SEC 1000000
42 
43 #include "Plugins/DynamicLoader/Darwin-Kernel/DynamicLoaderDarwinKernel.h"
44 #include "Plugins/DynamicLoader/Static/DynamicLoaderStatic.h"
45 #include "ProcessKDP.h"
46 #include "ProcessKDPLog.h"
47 #include "ThreadKDP.h"
48 
49 using namespace lldb;
50 using namespace lldb_private;
51 
52 namespace {
53 
54 static constexpr PropertyDefinition g_properties[] = {
55     {"packet-timeout", OptionValue::eTypeUInt64, true, 5, NULL, {},
56      "Specify the default packet timeout in seconds."}};
57 
58 enum { ePropertyPacketTimeout };
59 
60 class PluginProperties : public Properties {
61 public:
62   static ConstString GetSettingName() {
63     return ProcessKDP::GetPluginNameStatic();
64   }
65 
66   PluginProperties() : Properties() {
67     m_collection_sp.reset(new OptionValueProperties(GetSettingName()));
68     m_collection_sp->Initialize(g_properties);
69   }
70 
71   virtual ~PluginProperties() {}
72 
73   uint64_t GetPacketTimeout() {
74     const uint32_t idx = ePropertyPacketTimeout;
75     return m_collection_sp->GetPropertyAtIndexAsUInt64(
76         NULL, idx, g_properties[idx].default_uint_value);
77   }
78 };
79 
80 typedef std::shared_ptr<PluginProperties> ProcessKDPPropertiesSP;
81 
82 static const ProcessKDPPropertiesSP &GetGlobalPluginProperties() {
83   static ProcessKDPPropertiesSP g_settings_sp;
84   if (!g_settings_sp)
85     g_settings_sp.reset(new PluginProperties());
86   return g_settings_sp;
87 }
88 
89 } // anonymous namespace end
90 
91 static const lldb::tid_t g_kernel_tid = 1;
92 
93 ConstString ProcessKDP::GetPluginNameStatic() {
94   static ConstString g_name("kdp-remote");
95   return g_name;
96 }
97 
98 const char *ProcessKDP::GetPluginDescriptionStatic() {
99   return "KDP Remote protocol based debugging plug-in for darwin kernel "
100          "debugging.";
101 }
102 
103 void ProcessKDP::Terminate() {
104   PluginManager::UnregisterPlugin(ProcessKDP::CreateInstance);
105 }
106 
107 lldb::ProcessSP ProcessKDP::CreateInstance(TargetSP target_sp,
108                                            ListenerSP listener_sp,
109                                            const FileSpec *crash_file_path) {
110   lldb::ProcessSP process_sp;
111   if (crash_file_path == NULL)
112     process_sp.reset(new ProcessKDP(target_sp, listener_sp));
113   return process_sp;
114 }
115 
116 bool ProcessKDP::CanDebug(TargetSP target_sp, bool plugin_specified_by_name) {
117   if (plugin_specified_by_name)
118     return true;
119 
120   // For now we are just making sure the file exists for a given module
121   Module *exe_module = target_sp->GetExecutableModulePointer();
122   if (exe_module) {
123     const llvm::Triple &triple_ref = target_sp->GetArchitecture().GetTriple();
124     switch (triple_ref.getOS()) {
125     case llvm::Triple::Darwin: // Should use "macosx" for desktop and "ios" for
126                                // iOS, but accept darwin just in case
127     case llvm::Triple::MacOSX: // For desktop targets
128     case llvm::Triple::IOS:    // For arm targets
129     case llvm::Triple::TvOS:
130     case llvm::Triple::WatchOS:
131       if (triple_ref.getVendor() == llvm::Triple::Apple) {
132         ObjectFile *exe_objfile = exe_module->GetObjectFile();
133         if (exe_objfile->GetType() == ObjectFile::eTypeExecutable &&
134             exe_objfile->GetStrata() == ObjectFile::eStrataKernel)
135           return true;
136       }
137       break;
138 
139     default:
140       break;
141     }
142   }
143   return false;
144 }
145 
146 //----------------------------------------------------------------------
147 // ProcessKDP constructor
148 //----------------------------------------------------------------------
149 ProcessKDP::ProcessKDP(TargetSP target_sp, ListenerSP listener_sp)
150     : Process(target_sp, listener_sp),
151       m_comm("lldb.process.kdp-remote.communication"),
152       m_async_broadcaster(NULL, "lldb.process.kdp-remote.async-broadcaster"),
153       m_dyld_plugin_name(), m_kernel_load_addr(LLDB_INVALID_ADDRESS),
154       m_command_sp(), m_kernel_thread_wp() {
155   m_async_broadcaster.SetEventName(eBroadcastBitAsyncThreadShouldExit,
156                                    "async thread should exit");
157   m_async_broadcaster.SetEventName(eBroadcastBitAsyncContinue,
158                                    "async thread continue");
159   const uint64_t timeout_seconds =
160       GetGlobalPluginProperties()->GetPacketTimeout();
161   if (timeout_seconds > 0)
162     m_comm.SetPacketTimeout(std::chrono::seconds(timeout_seconds));
163 }
164 
165 //----------------------------------------------------------------------
166 // Destructor
167 //----------------------------------------------------------------------
168 ProcessKDP::~ProcessKDP() {
169   Clear();
170   // We need to call finalize on the process before destroying ourselves to
171   // make sure all of the broadcaster cleanup goes as planned. If we destruct
172   // this class, then Process::~Process() might have problems trying to fully
173   // destroy the broadcaster.
174   Finalize();
175 }
176 
177 //----------------------------------------------------------------------
178 // PluginInterface
179 //----------------------------------------------------------------------
180 lldb_private::ConstString ProcessKDP::GetPluginName() {
181   return GetPluginNameStatic();
182 }
183 
184 uint32_t ProcessKDP::GetPluginVersion() { return 1; }
185 
186 Status ProcessKDP::WillLaunch(Module *module) {
187   Status error;
188   error.SetErrorString("launching not supported in kdp-remote plug-in");
189   return error;
190 }
191 
192 Status ProcessKDP::WillAttachToProcessWithID(lldb::pid_t pid) {
193   Status error;
194   error.SetErrorString(
195       "attaching to a by process ID not supported in kdp-remote plug-in");
196   return error;
197 }
198 
199 Status ProcessKDP::WillAttachToProcessWithName(const char *process_name,
200                                                bool wait_for_launch) {
201   Status error;
202   error.SetErrorString(
203       "attaching to a by process name not supported in kdp-remote plug-in");
204   return error;
205 }
206 
207 bool ProcessKDP::GetHostArchitecture(ArchSpec &arch) {
208   uint32_t cpu = m_comm.GetCPUType();
209   if (cpu) {
210     uint32_t sub = m_comm.GetCPUSubtype();
211     arch.SetArchitecture(eArchTypeMachO, cpu, sub);
212     // Leave architecture vendor as unspecified unknown
213     arch.GetTriple().setVendor(llvm::Triple::UnknownVendor);
214     arch.GetTriple().setVendorName(llvm::StringRef());
215     return true;
216   }
217   arch.Clear();
218   return false;
219 }
220 
221 Status ProcessKDP::DoConnectRemote(Stream *strm, llvm::StringRef remote_url) {
222   Status error;
223 
224   // Don't let any JIT happen when doing KDP as we can't allocate memory and we
225   // don't want to be mucking with threads that might already be handling
226   // exceptions
227   SetCanJIT(false);
228 
229   if (remote_url.empty()) {
230     error.SetErrorStringWithFormat("empty connection URL");
231     return error;
232   }
233 
234   std::unique_ptr<ConnectionFileDescriptor> conn_ap(
235       new ConnectionFileDescriptor());
236   if (conn_ap.get()) {
237     // Only try once for now.
238     // TODO: check if we should be retrying?
239     const uint32_t max_retry_count = 1;
240     for (uint32_t retry_count = 0; retry_count < max_retry_count;
241          ++retry_count) {
242       if (conn_ap->Connect(remote_url, &error) == eConnectionStatusSuccess)
243         break;
244       usleep(100000);
245     }
246   }
247 
248   if (conn_ap->IsConnected()) {
249     const TCPSocket &socket =
250         static_cast<const TCPSocket &>(*conn_ap->GetReadObject());
251     const uint16_t reply_port = socket.GetLocalPortNumber();
252 
253     if (reply_port != 0) {
254       m_comm.SetConnection(conn_ap.release());
255 
256       if (m_comm.SendRequestReattach(reply_port)) {
257         if (m_comm.SendRequestConnect(reply_port, reply_port,
258                                       "Greetings from LLDB...")) {
259           m_comm.GetVersion();
260 
261           Target &target = GetTarget();
262           ArchSpec kernel_arch;
263           // The host architecture
264           GetHostArchitecture(kernel_arch);
265           ArchSpec target_arch = target.GetArchitecture();
266           // Merge in any unspecified stuff into the target architecture in
267           // case the target arch isn't set at all or incompletely.
268           target_arch.MergeFrom(kernel_arch);
269           target.SetArchitecture(target_arch);
270 
271           /* Get the kernel's UUID and load address via KDP_KERNELVERSION
272            * packet.  */
273           /* An EFI kdp session has neither UUID nor load address. */
274 
275           UUID kernel_uuid = m_comm.GetUUID();
276           addr_t kernel_load_addr = m_comm.GetLoadAddress();
277 
278           if (m_comm.RemoteIsEFI()) {
279             // Select an invalid plugin name for the dynamic loader so one
280             // doesn't get used since EFI does its own manual loading via
281             // python scripting
282             static ConstString g_none_dynamic_loader("none");
283             m_dyld_plugin_name = g_none_dynamic_loader;
284 
285             if (kernel_uuid.IsValid()) {
286               // If EFI passed in a UUID= try to lookup UUID The slide will not
287               // be provided. But the UUID lookup will be used to launch EFI
288               // debug scripts from the dSYM, that can load all of the symbols.
289               ModuleSpec module_spec;
290               module_spec.GetUUID() = kernel_uuid;
291               module_spec.GetArchitecture() = target.GetArchitecture();
292 
293               // Lookup UUID locally, before attempting dsymForUUID like action
294               module_spec.GetSymbolFileSpec() =
295                   Symbols::LocateExecutableSymbolFile(module_spec);
296               if (module_spec.GetSymbolFileSpec()) {
297                 ModuleSpec executable_module_spec =
298                     Symbols::LocateExecutableObjectFile(module_spec);
299                 if (FileSystem::Instance().Exists(
300                         executable_module_spec.GetFileSpec())) {
301                   module_spec.GetFileSpec() =
302                       executable_module_spec.GetFileSpec();
303                 }
304               }
305               if (!module_spec.GetSymbolFileSpec() ||
306                   !module_spec.GetSymbolFileSpec())
307                 Symbols::DownloadObjectAndSymbolFile(module_spec, true);
308 
309               if (FileSystem::Instance().Exists(module_spec.GetFileSpec())) {
310                 ModuleSP module_sp(new Module(module_spec));
311                 if (module_sp.get() && module_sp->GetObjectFile()) {
312                   // Get the current target executable
313                   ModuleSP exe_module_sp(target.GetExecutableModule());
314 
315                   // Make sure you don't already have the right module loaded
316                   // and they will be uniqued
317                   if (exe_module_sp.get() != module_sp.get())
318                     target.SetExecutableModule(module_sp, eLoadDependentsNo);
319                 }
320               }
321             }
322           } else if (m_comm.RemoteIsDarwinKernel()) {
323             m_dyld_plugin_name =
324                 DynamicLoaderDarwinKernel::GetPluginNameStatic();
325             if (kernel_load_addr != LLDB_INVALID_ADDRESS) {
326               m_kernel_load_addr = kernel_load_addr;
327             }
328           }
329 
330           // Set the thread ID
331           UpdateThreadListIfNeeded();
332           SetID(1);
333           GetThreadList();
334           SetPrivateState(eStateStopped);
335           StreamSP async_strm_sp(target.GetDebugger().GetAsyncOutputStream());
336           if (async_strm_sp) {
337             const char *cstr;
338             if ((cstr = m_comm.GetKernelVersion()) != NULL) {
339               async_strm_sp->Printf("Version: %s\n", cstr);
340               async_strm_sp->Flush();
341             }
342             //                      if ((cstr = m_comm.GetImagePath ()) != NULL)
343             //                      {
344             //                          async_strm_sp->Printf ("Image Path:
345             //                          %s\n", cstr);
346             //                          async_strm_sp->Flush();
347             //                      }
348           }
349         } else {
350           error.SetErrorString("KDP_REATTACH failed");
351         }
352       } else {
353         error.SetErrorString("KDP_REATTACH failed");
354       }
355     } else {
356       error.SetErrorString("invalid reply port from UDP connection");
357     }
358   } else {
359     if (error.Success())
360       error.SetErrorStringWithFormat("failed to connect to '%s'",
361                                      remote_url.str().c_str());
362   }
363   if (error.Fail())
364     m_comm.Disconnect();
365 
366   return error;
367 }
368 
369 //----------------------------------------------------------------------
370 // Process Control
371 //----------------------------------------------------------------------
372 Status ProcessKDP::DoLaunch(Module *exe_module,
373                             ProcessLaunchInfo &launch_info) {
374   Status error;
375   error.SetErrorString("launching not supported in kdp-remote plug-in");
376   return error;
377 }
378 
379 Status
380 ProcessKDP::DoAttachToProcessWithID(lldb::pid_t attach_pid,
381                                     const ProcessAttachInfo &attach_info) {
382   Status error;
383   error.SetErrorString(
384       "attach to process by ID is not supported in kdp remote debugging");
385   return error;
386 }
387 
388 Status
389 ProcessKDP::DoAttachToProcessWithName(const char *process_name,
390                                       const ProcessAttachInfo &attach_info) {
391   Status error;
392   error.SetErrorString(
393       "attach to process by name is not supported in kdp remote debugging");
394   return error;
395 }
396 
397 void ProcessKDP::DidAttach(ArchSpec &process_arch) {
398   Process::DidAttach(process_arch);
399 
400   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_PROCESS));
401   if (log)
402     log->Printf("ProcessKDP::DidAttach()");
403   if (GetID() != LLDB_INVALID_PROCESS_ID) {
404     GetHostArchitecture(process_arch);
405   }
406 }
407 
408 addr_t ProcessKDP::GetImageInfoAddress() { return m_kernel_load_addr; }
409 
410 lldb_private::DynamicLoader *ProcessKDP::GetDynamicLoader() {
411   if (m_dyld_ap.get() == NULL)
412     m_dyld_ap.reset(DynamicLoader::FindPlugin(
413         this,
414         m_dyld_plugin_name.IsEmpty() ? NULL : m_dyld_plugin_name.GetCString()));
415   return m_dyld_ap.get();
416 }
417 
418 Status ProcessKDP::WillResume() { return Status(); }
419 
420 Status ProcessKDP::DoResume() {
421   Status error;
422   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_PROCESS));
423   // Only start the async thread if we try to do any process control
424   if (!m_async_thread.IsJoinable())
425     StartAsyncThread();
426 
427   bool resume = false;
428 
429   // With KDP there is only one thread we can tell what to do
430   ThreadSP kernel_thread_sp(m_thread_list.FindThreadByProtocolID(g_kernel_tid));
431 
432   if (kernel_thread_sp) {
433     const StateType thread_resume_state =
434         kernel_thread_sp->GetTemporaryResumeState();
435 
436     if (log)
437       log->Printf("ProcessKDP::DoResume() thread_resume_state = %s",
438                   StateAsCString(thread_resume_state));
439     switch (thread_resume_state) {
440     case eStateSuspended:
441       // Nothing to do here when a thread will stay suspended we just leave the
442       // CPU mask bit set to zero for the thread
443       if (log)
444         log->Printf("ProcessKDP::DoResume() = suspended???");
445       break;
446 
447     case eStateStepping: {
448       lldb::RegisterContextSP reg_ctx_sp(
449           kernel_thread_sp->GetRegisterContext());
450 
451       if (reg_ctx_sp) {
452         if (log)
453           log->Printf(
454               "ProcessKDP::DoResume () reg_ctx_sp->HardwareSingleStep (true);");
455         reg_ctx_sp->HardwareSingleStep(true);
456         resume = true;
457       } else {
458         error.SetErrorStringWithFormat(
459             "KDP thread 0x%llx has no register context",
460             kernel_thread_sp->GetID());
461       }
462     } break;
463 
464     case eStateRunning: {
465       lldb::RegisterContextSP reg_ctx_sp(
466           kernel_thread_sp->GetRegisterContext());
467 
468       if (reg_ctx_sp) {
469         if (log)
470           log->Printf("ProcessKDP::DoResume () reg_ctx_sp->HardwareSingleStep "
471                       "(false);");
472         reg_ctx_sp->HardwareSingleStep(false);
473         resume = true;
474       } else {
475         error.SetErrorStringWithFormat(
476             "KDP thread 0x%llx has no register context",
477             kernel_thread_sp->GetID());
478       }
479     } break;
480 
481     default:
482       // The only valid thread resume states are listed above
483       llvm_unreachable("invalid thread resume state");
484     }
485   }
486 
487   if (resume) {
488     if (log)
489       log->Printf("ProcessKDP::DoResume () sending resume");
490 
491     if (m_comm.SendRequestResume()) {
492       m_async_broadcaster.BroadcastEvent(eBroadcastBitAsyncContinue);
493       SetPrivateState(eStateRunning);
494     } else
495       error.SetErrorString("KDP resume failed");
496   } else {
497     error.SetErrorString("kernel thread is suspended");
498   }
499 
500   return error;
501 }
502 
503 lldb::ThreadSP ProcessKDP::GetKernelThread() {
504   // KDP only tells us about one thread/core. Any other threads will usually
505   // be the ones that are read from memory by the OS plug-ins.
506 
507   ThreadSP thread_sp(m_kernel_thread_wp.lock());
508   if (!thread_sp) {
509     thread_sp.reset(new ThreadKDP(*this, g_kernel_tid));
510     m_kernel_thread_wp = thread_sp;
511   }
512   return thread_sp;
513 }
514 
515 bool ProcessKDP::UpdateThreadList(ThreadList &old_thread_list,
516                                   ThreadList &new_thread_list) {
517   // locker will keep a mutex locked until it goes out of scope
518   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_THREAD));
519   LLDB_LOGV(log, "pid = {0}", GetID());
520 
521   // Even though there is a CPU mask, it doesn't mean we can see each CPU
522   // individually, there is really only one. Lets call this thread 1.
523   ThreadSP thread_sp(
524       old_thread_list.FindThreadByProtocolID(g_kernel_tid, false));
525   if (!thread_sp)
526     thread_sp = GetKernelThread();
527   new_thread_list.AddThread(thread_sp);
528 
529   return new_thread_list.GetSize(false) > 0;
530 }
531 
532 void ProcessKDP::RefreshStateAfterStop() {
533   // Let all threads recover from stopping and do any clean up based on the
534   // previous thread state (if any).
535   m_thread_list.RefreshStateAfterStop();
536 }
537 
538 Status ProcessKDP::DoHalt(bool &caused_stop) {
539   Status error;
540 
541   if (m_comm.IsRunning()) {
542     if (m_destroy_in_process) {
543       // If we are attempting to destroy, we need to not return an error to Halt
544       // or DoDestroy won't get called. We are also currently running, so send
545       // a process stopped event
546       SetPrivateState(eStateStopped);
547     } else {
548       error.SetErrorString("KDP cannot interrupt a running kernel");
549     }
550   }
551   return error;
552 }
553 
554 Status ProcessKDP::DoDetach(bool keep_stopped) {
555   Status error;
556   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_PROCESS));
557   if (log)
558     log->Printf("ProcessKDP::DoDetach(keep_stopped = %i)", keep_stopped);
559 
560   if (m_comm.IsRunning()) {
561     // We are running and we can't interrupt a running kernel, so we need to
562     // just close the connection to the kernel and hope for the best
563   } else {
564     // If we are going to keep the target stopped, then don't send the
565     // disconnect message.
566     if (!keep_stopped && m_comm.IsConnected()) {
567       const bool success = m_comm.SendRequestDisconnect();
568       if (log) {
569         if (success)
570           log->PutCString(
571               "ProcessKDP::DoDetach() detach packet sent successfully");
572         else
573           log->PutCString(
574               "ProcessKDP::DoDetach() connection channel shutdown failed");
575       }
576       m_comm.Disconnect();
577     }
578   }
579   StopAsyncThread();
580   m_comm.Clear();
581 
582   SetPrivateState(eStateDetached);
583   ResumePrivateStateThread();
584 
585   // KillDebugserverProcess ();
586   return error;
587 }
588 
589 Status ProcessKDP::DoDestroy() {
590   // For KDP there really is no difference between destroy and detach
591   bool keep_stopped = false;
592   return DoDetach(keep_stopped);
593 }
594 
595 //------------------------------------------------------------------
596 // Process Queries
597 //------------------------------------------------------------------
598 
599 bool ProcessKDP::IsAlive() {
600   return m_comm.IsConnected() && Process::IsAlive();
601 }
602 
603 //------------------------------------------------------------------
604 // Process Memory
605 //------------------------------------------------------------------
606 size_t ProcessKDP::DoReadMemory(addr_t addr, void *buf, size_t size,
607                                 Status &error) {
608   uint8_t *data_buffer = (uint8_t *)buf;
609   if (m_comm.IsConnected()) {
610     const size_t max_read_size = 512;
611     size_t total_bytes_read = 0;
612 
613     // Read the requested amount of memory in 512 byte chunks
614     while (total_bytes_read < size) {
615       size_t bytes_to_read_this_request = size - total_bytes_read;
616       if (bytes_to_read_this_request > max_read_size) {
617         bytes_to_read_this_request = max_read_size;
618       }
619       size_t bytes_read = m_comm.SendRequestReadMemory(
620           addr + total_bytes_read, data_buffer + total_bytes_read,
621           bytes_to_read_this_request, error);
622       total_bytes_read += bytes_read;
623       if (error.Fail() || bytes_read == 0) {
624         return total_bytes_read;
625       }
626     }
627 
628     return total_bytes_read;
629   }
630   error.SetErrorString("not connected");
631   return 0;
632 }
633 
634 size_t ProcessKDP::DoWriteMemory(addr_t addr, const void *buf, size_t size,
635                                  Status &error) {
636   if (m_comm.IsConnected())
637     return m_comm.SendRequestWriteMemory(addr, buf, size, error);
638   error.SetErrorString("not connected");
639   return 0;
640 }
641 
642 lldb::addr_t ProcessKDP::DoAllocateMemory(size_t size, uint32_t permissions,
643                                           Status &error) {
644   error.SetErrorString(
645       "memory allocation not supported in kdp remote debugging");
646   return LLDB_INVALID_ADDRESS;
647 }
648 
649 Status ProcessKDP::DoDeallocateMemory(lldb::addr_t addr) {
650   Status error;
651   error.SetErrorString(
652       "memory deallocation not supported in kdp remote debugging");
653   return error;
654 }
655 
656 Status ProcessKDP::EnableBreakpointSite(BreakpointSite *bp_site) {
657   if (m_comm.LocalBreakpointsAreSupported()) {
658     Status error;
659     if (!bp_site->IsEnabled()) {
660       if (m_comm.SendRequestBreakpoint(true, bp_site->GetLoadAddress())) {
661         bp_site->SetEnabled(true);
662         bp_site->SetType(BreakpointSite::eExternal);
663       } else {
664         error.SetErrorString("KDP set breakpoint failed");
665       }
666     }
667     return error;
668   }
669   return EnableSoftwareBreakpoint(bp_site);
670 }
671 
672 Status ProcessKDP::DisableBreakpointSite(BreakpointSite *bp_site) {
673   if (m_comm.LocalBreakpointsAreSupported()) {
674     Status error;
675     if (bp_site->IsEnabled()) {
676       BreakpointSite::Type bp_type = bp_site->GetType();
677       if (bp_type == BreakpointSite::eExternal) {
678         if (m_destroy_in_process && m_comm.IsRunning()) {
679           // We are trying to destroy our connection and we are running
680           bp_site->SetEnabled(false);
681         } else {
682           if (m_comm.SendRequestBreakpoint(false, bp_site->GetLoadAddress()))
683             bp_site->SetEnabled(false);
684           else
685             error.SetErrorString("KDP remove breakpoint failed");
686         }
687       } else {
688         error = DisableSoftwareBreakpoint(bp_site);
689       }
690     }
691     return error;
692   }
693   return DisableSoftwareBreakpoint(bp_site);
694 }
695 
696 Status ProcessKDP::EnableWatchpoint(Watchpoint *wp, bool notify) {
697   Status error;
698   error.SetErrorString(
699       "watchpoints are not supported in kdp remote debugging");
700   return error;
701 }
702 
703 Status ProcessKDP::DisableWatchpoint(Watchpoint *wp, bool notify) {
704   Status error;
705   error.SetErrorString(
706       "watchpoints are not supported in kdp remote debugging");
707   return error;
708 }
709 
710 void ProcessKDP::Clear() { m_thread_list.Clear(); }
711 
712 Status ProcessKDP::DoSignal(int signo) {
713   Status error;
714   error.SetErrorString(
715       "sending signals is not supported in kdp remote debugging");
716   return error;
717 }
718 
719 void ProcessKDP::Initialize() {
720   static llvm::once_flag g_once_flag;
721 
722   llvm::call_once(g_once_flag, []() {
723     PluginManager::RegisterPlugin(GetPluginNameStatic(),
724                                   GetPluginDescriptionStatic(), CreateInstance,
725                                   DebuggerInitialize);
726 
727     ProcessKDPLog::Initialize();
728   });
729 }
730 
731 void ProcessKDP::DebuggerInitialize(lldb_private::Debugger &debugger) {
732   if (!PluginManager::GetSettingForProcessPlugin(
733           debugger, PluginProperties::GetSettingName())) {
734     const bool is_global_setting = true;
735     PluginManager::CreateSettingForProcessPlugin(
736         debugger, GetGlobalPluginProperties()->GetValueProperties(),
737         ConstString("Properties for the kdp-remote process plug-in."),
738         is_global_setting);
739   }
740 }
741 
742 bool ProcessKDP::StartAsyncThread() {
743   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_PROCESS));
744 
745   if (log)
746     log->Printf("ProcessKDP::StartAsyncThread ()");
747 
748   if (m_async_thread.IsJoinable())
749     return true;
750 
751   m_async_thread = ThreadLauncher::LaunchThread(
752       "<lldb.process.kdp-remote.async>", ProcessKDP::AsyncThread, this, NULL);
753   return m_async_thread.IsJoinable();
754 }
755 
756 void ProcessKDP::StopAsyncThread() {
757   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_PROCESS));
758 
759   if (log)
760     log->Printf("ProcessKDP::StopAsyncThread ()");
761 
762   m_async_broadcaster.BroadcastEvent(eBroadcastBitAsyncThreadShouldExit);
763 
764   // Stop the stdio thread
765   if (m_async_thread.IsJoinable())
766     m_async_thread.Join(nullptr);
767 }
768 
769 void *ProcessKDP::AsyncThread(void *arg) {
770   ProcessKDP *process = (ProcessKDP *)arg;
771 
772   const lldb::pid_t pid = process->GetID();
773 
774   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_PROCESS));
775   if (log)
776     log->Printf("ProcessKDP::AsyncThread (arg = %p, pid = %" PRIu64
777                 ") thread starting...",
778                 arg, pid);
779 
780   ListenerSP listener_sp(Listener::MakeListener("ProcessKDP::AsyncThread"));
781   EventSP event_sp;
782   const uint32_t desired_event_mask =
783       eBroadcastBitAsyncContinue | eBroadcastBitAsyncThreadShouldExit;
784 
785   if (listener_sp->StartListeningForEvents(&process->m_async_broadcaster,
786                                            desired_event_mask) ==
787       desired_event_mask) {
788     bool done = false;
789     while (!done) {
790       if (log)
791         log->Printf("ProcessKDP::AsyncThread (pid = %" PRIu64
792                     ") listener.WaitForEvent (NULL, event_sp)...",
793                     pid);
794       if (listener_sp->GetEvent(event_sp, llvm::None)) {
795         uint32_t event_type = event_sp->GetType();
796         if (log)
797           log->Printf("ProcessKDP::AsyncThread (pid = %" PRIu64
798                       ") Got an event of type: %d...",
799                       pid, event_type);
800 
801         // When we are running, poll for 1 second to try and get an exception
802         // to indicate the process has stopped. If we don't get one, check to
803         // make sure no one asked us to exit
804         bool is_running = false;
805         DataExtractor exc_reply_packet;
806         do {
807           switch (event_type) {
808           case eBroadcastBitAsyncContinue: {
809             is_running = true;
810             if (process->m_comm.WaitForPacketWithTimeoutMicroSeconds(
811                     exc_reply_packet, 1 * USEC_PER_SEC)) {
812               ThreadSP thread_sp(process->GetKernelThread());
813               if (thread_sp) {
814                 lldb::RegisterContextSP reg_ctx_sp(
815                     thread_sp->GetRegisterContext());
816                 if (reg_ctx_sp)
817                   reg_ctx_sp->InvalidateAllRegisters();
818                 static_cast<ThreadKDP *>(thread_sp.get())
819                     ->SetStopInfoFrom_KDP_EXCEPTION(exc_reply_packet);
820               }
821 
822               // TODO: parse the stop reply packet
823               is_running = false;
824               process->SetPrivateState(eStateStopped);
825             } else {
826               // Check to see if we are supposed to exit. There is no way to
827               // interrupt a running kernel, so all we can do is wait for an
828               // exception or detach...
829               if (listener_sp->GetEvent(event_sp,
830                                         std::chrono::microseconds(0))) {
831                 // We got an event, go through the loop again
832                 event_type = event_sp->GetType();
833               }
834             }
835           } break;
836 
837           case eBroadcastBitAsyncThreadShouldExit:
838             if (log)
839               log->Printf("ProcessKDP::AsyncThread (pid = %" PRIu64
840                           ") got eBroadcastBitAsyncThreadShouldExit...",
841                           pid);
842             done = true;
843             is_running = false;
844             break;
845 
846           default:
847             if (log)
848               log->Printf("ProcessKDP::AsyncThread (pid = %" PRIu64
849                           ") got unknown event 0x%8.8x",
850                           pid, event_type);
851             done = true;
852             is_running = false;
853             break;
854           }
855         } while (is_running);
856       } else {
857         if (log)
858           log->Printf("ProcessKDP::AsyncThread (pid = %" PRIu64
859                       ") listener.WaitForEvent (NULL, event_sp) => false",
860                       pid);
861         done = true;
862       }
863     }
864   }
865 
866   if (log)
867     log->Printf("ProcessKDP::AsyncThread (arg = %p, pid = %" PRIu64
868                 ") thread exiting...",
869                 arg, pid);
870 
871   process->m_async_thread.Reset();
872   return NULL;
873 }
874 
875 class CommandObjectProcessKDPPacketSend : public CommandObjectParsed {
876 private:
877   OptionGroupOptions m_option_group;
878   OptionGroupUInt64 m_command_byte;
879   OptionGroupString m_packet_data;
880 
881   virtual Options *GetOptions() { return &m_option_group; }
882 
883 public:
884   CommandObjectProcessKDPPacketSend(CommandInterpreter &interpreter)
885       : CommandObjectParsed(interpreter, "process plugin packet send",
886                             "Send a custom packet through the KDP protocol by "
887                             "specifying the command byte and the packet "
888                             "payload data. A packet will be sent with a "
889                             "correct header and payload, and the raw result "
890                             "bytes will be displayed as a string value. ",
891                             NULL),
892         m_option_group(),
893         m_command_byte(LLDB_OPT_SET_1, true, "command", 'c', 0, eArgTypeNone,
894                        "Specify the command byte to use when sending the KDP "
895                        "request packet.",
896                        0),
897         m_packet_data(LLDB_OPT_SET_1, false, "payload", 'p', 0, eArgTypeNone,
898                       "Specify packet payload bytes as a hex ASCII string with "
899                       "no spaces or hex prefixes.",
900                       NULL) {
901     m_option_group.Append(&m_command_byte, LLDB_OPT_SET_ALL, LLDB_OPT_SET_1);
902     m_option_group.Append(&m_packet_data, LLDB_OPT_SET_ALL, LLDB_OPT_SET_1);
903     m_option_group.Finalize();
904   }
905 
906   ~CommandObjectProcessKDPPacketSend() {}
907 
908   bool DoExecute(Args &command, CommandReturnObject &result) {
909     const size_t argc = command.GetArgumentCount();
910     if (argc == 0) {
911       if (!m_command_byte.GetOptionValue().OptionWasSet()) {
912         result.AppendError(
913             "the --command option must be set to a valid command byte");
914         result.SetStatus(eReturnStatusFailed);
915       } else {
916         const uint64_t command_byte =
917             m_command_byte.GetOptionValue().GetUInt64Value(0);
918         if (command_byte > 0 && command_byte <= UINT8_MAX) {
919           ProcessKDP *process =
920               (ProcessKDP *)m_interpreter.GetExecutionContext().GetProcessPtr();
921           if (process) {
922             const StateType state = process->GetState();
923 
924             if (StateIsStoppedState(state, true)) {
925               std::vector<uint8_t> payload_bytes;
926               const char *ascii_hex_bytes_cstr =
927                   m_packet_data.GetOptionValue().GetCurrentValue();
928               if (ascii_hex_bytes_cstr && ascii_hex_bytes_cstr[0]) {
929                 StringExtractor extractor(ascii_hex_bytes_cstr);
930                 const size_t ascii_hex_bytes_cstr_len =
931                     extractor.GetStringRef().size();
932                 if (ascii_hex_bytes_cstr_len & 1) {
933                   result.AppendErrorWithFormat("payload data must contain an "
934                                                "even number of ASCII hex "
935                                                "characters: '%s'",
936                                                ascii_hex_bytes_cstr);
937                   result.SetStatus(eReturnStatusFailed);
938                   return false;
939                 }
940                 payload_bytes.resize(ascii_hex_bytes_cstr_len / 2);
941                 if (extractor.GetHexBytes(payload_bytes, '\xdd') !=
942                     payload_bytes.size()) {
943                   result.AppendErrorWithFormat("payload data must only contain "
944                                                "ASCII hex characters (no "
945                                                "spaces or hex prefixes): '%s'",
946                                                ascii_hex_bytes_cstr);
947                   result.SetStatus(eReturnStatusFailed);
948                   return false;
949                 }
950               }
951               Status error;
952               DataExtractor reply;
953               process->GetCommunication().SendRawRequest(
954                   command_byte,
955                   payload_bytes.empty() ? NULL : payload_bytes.data(),
956                   payload_bytes.size(), reply, error);
957 
958               if (error.Success()) {
959                 // Copy the binary bytes into a hex ASCII string for the result
960                 StreamString packet;
961                 packet.PutBytesAsRawHex8(
962                     reply.GetDataStart(), reply.GetByteSize(),
963                     endian::InlHostByteOrder(), endian::InlHostByteOrder());
964                 result.AppendMessage(packet.GetString());
965                 result.SetStatus(eReturnStatusSuccessFinishResult);
966                 return true;
967               } else {
968                 const char *error_cstr = error.AsCString();
969                 if (error_cstr && error_cstr[0])
970                   result.AppendError(error_cstr);
971                 else
972                   result.AppendErrorWithFormat("unknown error 0x%8.8x",
973                                                error.GetError());
974                 result.SetStatus(eReturnStatusFailed);
975                 return false;
976               }
977             } else {
978               result.AppendErrorWithFormat("process must be stopped in order "
979                                            "to send KDP packets, state is %s",
980                                            StateAsCString(state));
981               result.SetStatus(eReturnStatusFailed);
982             }
983           } else {
984             result.AppendError("invalid process");
985             result.SetStatus(eReturnStatusFailed);
986           }
987         } else {
988           result.AppendErrorWithFormat("invalid command byte 0x%" PRIx64
989                                        ", valid values are 1 - 255",
990                                        command_byte);
991           result.SetStatus(eReturnStatusFailed);
992         }
993       }
994     } else {
995       result.AppendErrorWithFormat("'%s' takes no arguments, only options.",
996                                    m_cmd_name.c_str());
997       result.SetStatus(eReturnStatusFailed);
998     }
999     return false;
1000   }
1001 };
1002 
1003 class CommandObjectProcessKDPPacket : public CommandObjectMultiword {
1004 private:
1005 public:
1006   CommandObjectProcessKDPPacket(CommandInterpreter &interpreter)
1007       : CommandObjectMultiword(interpreter, "process plugin packet",
1008                                "Commands that deal with KDP remote packets.",
1009                                NULL) {
1010     LoadSubCommand(
1011         "send",
1012         CommandObjectSP(new CommandObjectProcessKDPPacketSend(interpreter)));
1013   }
1014 
1015   ~CommandObjectProcessKDPPacket() {}
1016 };
1017 
1018 class CommandObjectMultiwordProcessKDP : public CommandObjectMultiword {
1019 public:
1020   CommandObjectMultiwordProcessKDP(CommandInterpreter &interpreter)
1021       : CommandObjectMultiword(
1022             interpreter, "process plugin",
1023             "Commands for operating on a ProcessKDP process.",
1024             "process plugin <subcommand> [<subcommand-options>]") {
1025     LoadSubCommand("packet", CommandObjectSP(new CommandObjectProcessKDPPacket(
1026                                  interpreter)));
1027   }
1028 
1029   ~CommandObjectMultiwordProcessKDP() {}
1030 };
1031 
1032 CommandObject *ProcessKDP::GetPluginCommandObject() {
1033   if (!m_command_sp)
1034     m_command_sp.reset(new CommandObjectMultiwordProcessKDP(
1035         GetTarget().GetDebugger().GetCommandInterpreter()));
1036   return m_command_sp.get();
1037 }
1038