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 // C Includes
11 #include <errno.h>
12 #include <stdlib.h>
13 
14 // C++ Includes
15 #include <mutex>
16 
17 // Other libraries and framework includes
18 #include "lldb/Core/Debugger.h"
19 #include "lldb/Core/Module.h"
20 #include "lldb/Core/ModuleSpec.h"
21 #include "lldb/Core/PluginManager.h"
22 #include "lldb/Host/ConnectionFileDescriptor.h"
23 #include "lldb/Host/Host.h"
24 #include "lldb/Host/Symbols.h"
25 #include "lldb/Host/ThreadLauncher.h"
26 #include "lldb/Host/common/TCPSocket.h"
27 #include "lldb/Interpreter/CommandInterpreter.h"
28 #include "lldb/Interpreter/CommandObject.h"
29 #include "lldb/Interpreter/CommandObjectMultiword.h"
30 #include "lldb/Interpreter/CommandReturnObject.h"
31 #include "lldb/Interpreter/OptionGroupString.h"
32 #include "lldb/Interpreter/OptionGroupUInt64.h"
33 #include "lldb/Interpreter/OptionValueProperties.h"
34 #include "lldb/Symbol/ObjectFile.h"
35 #include "lldb/Target/RegisterContext.h"
36 #include "lldb/Target/Target.h"
37 #include "lldb/Target/Thread.h"
38 #include "lldb/Utility/State.h"
39 #include "lldb/Utility/StringExtractor.h"
40 #include "lldb/Utility/UUID.h"
41 
42 #include "llvm/Support/Threading.h"
43 
44 #define USEC_PER_SEC 1000000
45 
46 // Project includes
47 #include "Plugins/DynamicLoader/Darwin-Kernel/DynamicLoaderDarwinKernel.h"
48 #include "Plugins/DynamicLoader/Static/DynamicLoaderStatic.h"
49 #include "ProcessKDP.h"
50 #include "ProcessKDPLog.h"
51 #include "ThreadKDP.h"
52 
53 using namespace lldb;
54 using namespace lldb_private;
55 
56 namespace {
57 
58 static PropertyDefinition g_properties[] = {
59     {"packet-timeout", OptionValue::eTypeUInt64, true, 5, NULL, NULL,
60      "Specify the default packet timeout in seconds."},
61     {NULL, OptionValue::eTypeInvalid, false, 0, NULL, NULL, NULL}};
62 
63 enum { ePropertyPacketTimeout };
64 
65 class PluginProperties : public Properties {
66 public:
67   static ConstString GetSettingName() {
68     return ProcessKDP::GetPluginNameStatic();
69   }
70 
71   PluginProperties() : Properties() {
72     m_collection_sp.reset(new OptionValueProperties(GetSettingName()));
73     m_collection_sp->Initialize(g_properties);
74   }
75 
76   virtual ~PluginProperties() {}
77 
78   uint64_t GetPacketTimeout() {
79     const uint32_t idx = ePropertyPacketTimeout;
80     return m_collection_sp->GetPropertyAtIndexAsUInt64(
81         NULL, idx, g_properties[idx].default_uint_value);
82   }
83 };
84 
85 typedef std::shared_ptr<PluginProperties> ProcessKDPPropertiesSP;
86 
87 static const ProcessKDPPropertiesSP &GetGlobalPluginProperties() {
88   static ProcessKDPPropertiesSP g_settings_sp;
89   if (!g_settings_sp)
90     g_settings_sp.reset(new PluginProperties());
91   return g_settings_sp;
92 }
93 
94 } // anonymous namespace end
95 
96 static const lldb::tid_t g_kernel_tid = 1;
97 
98 ConstString ProcessKDP::GetPluginNameStatic() {
99   static ConstString g_name("kdp-remote");
100   return g_name;
101 }
102 
103 const char *ProcessKDP::GetPluginDescriptionStatic() {
104   return "KDP Remote protocol based debugging plug-in for darwin kernel "
105          "debugging.";
106 }
107 
108 void ProcessKDP::Terminate() {
109   PluginManager::UnregisterPlugin(ProcessKDP::CreateInstance);
110 }
111 
112 lldb::ProcessSP ProcessKDP::CreateInstance(TargetSP target_sp,
113                                            ListenerSP listener_sp,
114                                            const FileSpec *crash_file_path) {
115   lldb::ProcessSP process_sp;
116   if (crash_file_path == NULL)
117     process_sp.reset(new ProcessKDP(target_sp, listener_sp));
118   return process_sp;
119 }
120 
121 bool ProcessKDP::CanDebug(TargetSP target_sp, bool plugin_specified_by_name) {
122   if (plugin_specified_by_name)
123     return true;
124 
125   // For now we are just making sure the file exists for a given module
126   Module *exe_module = target_sp->GetExecutableModulePointer();
127   if (exe_module) {
128     const llvm::Triple &triple_ref = target_sp->GetArchitecture().GetTriple();
129     switch (triple_ref.getOS()) {
130     case llvm::Triple::Darwin: // Should use "macosx" for desktop and "ios" for
131                                // iOS, but accept darwin just in case
132     case llvm::Triple::MacOSX: // For desktop targets
133     case llvm::Triple::IOS:    // For arm targets
134     case llvm::Triple::TvOS:
135     case llvm::Triple::WatchOS:
136       if (triple_ref.getVendor() == llvm::Triple::Apple) {
137         ObjectFile *exe_objfile = exe_module->GetObjectFile();
138         if (exe_objfile->GetType() == ObjectFile::eTypeExecutable &&
139             exe_objfile->GetStrata() == ObjectFile::eStrataKernel)
140           return true;
141       }
142       break;
143 
144     default:
145       break;
146     }
147   }
148   return false;
149 }
150 
151 //----------------------------------------------------------------------
152 // ProcessKDP constructor
153 //----------------------------------------------------------------------
154 ProcessKDP::ProcessKDP(TargetSP target_sp, ListenerSP listener_sp)
155     : Process(target_sp, listener_sp),
156       m_comm("lldb.process.kdp-remote.communication"),
157       m_async_broadcaster(NULL, "lldb.process.kdp-remote.async-broadcaster"),
158       m_dyld_plugin_name(), m_kernel_load_addr(LLDB_INVALID_ADDRESS),
159       m_command_sp(), m_kernel_thread_wp() {
160   m_async_broadcaster.SetEventName(eBroadcastBitAsyncThreadShouldExit,
161                                    "async thread should exit");
162   m_async_broadcaster.SetEventName(eBroadcastBitAsyncContinue,
163                                    "async thread continue");
164   const uint64_t timeout_seconds =
165       GetGlobalPluginProperties()->GetPacketTimeout();
166   if (timeout_seconds > 0)
167     m_comm.SetPacketTimeout(std::chrono::seconds(timeout_seconds));
168 }
169 
170 //----------------------------------------------------------------------
171 // Destructor
172 //----------------------------------------------------------------------
173 ProcessKDP::~ProcessKDP() {
174   Clear();
175   // We need to call finalize on the process before destroying ourselves to
176   // make sure all of the broadcaster cleanup goes as planned. If we destruct
177   // this class, then Process::~Process() might have problems trying to fully
178   // destroy the broadcaster.
179   Finalize();
180 }
181 
182 //----------------------------------------------------------------------
183 // PluginInterface
184 //----------------------------------------------------------------------
185 lldb_private::ConstString ProcessKDP::GetPluginName() {
186   return GetPluginNameStatic();
187 }
188 
189 uint32_t ProcessKDP::GetPluginVersion() { return 1; }
190 
191 Status ProcessKDP::WillLaunch(Module *module) {
192   Status error;
193   error.SetErrorString("launching not supported in kdp-remote plug-in");
194   return error;
195 }
196 
197 Status ProcessKDP::WillAttachToProcessWithID(lldb::pid_t pid) {
198   Status error;
199   error.SetErrorString(
200       "attaching to a by process ID not supported in kdp-remote plug-in");
201   return error;
202 }
203 
204 Status ProcessKDP::WillAttachToProcessWithName(const char *process_name,
205                                                bool wait_for_launch) {
206   Status error;
207   error.SetErrorString(
208       "attaching to a by process name not supported in kdp-remote plug-in");
209   return error;
210 }
211 
212 bool ProcessKDP::GetHostArchitecture(ArchSpec &arch) {
213   uint32_t cpu = m_comm.GetCPUType();
214   if (cpu) {
215     uint32_t sub = m_comm.GetCPUSubtype();
216     arch.SetArchitecture(eArchTypeMachO, cpu, sub);
217     // Leave architecture vendor as unspecified unknown
218     arch.GetTriple().setVendor(llvm::Triple::UnknownVendor);
219     arch.GetTriple().setVendorName(llvm::StringRef());
220     return true;
221   }
222   arch.Clear();
223   return false;
224 }
225 
226 Status ProcessKDP::DoConnectRemote(Stream *strm, llvm::StringRef remote_url) {
227   Status error;
228 
229   // Don't let any JIT happen when doing KDP as we can't allocate memory and we
230   // don't want to be mucking with threads that might already be handling
231   // exceptions
232   SetCanJIT(false);
233 
234   if (remote_url.empty()) {
235     error.SetErrorStringWithFormat("empty connection URL");
236     return error;
237   }
238 
239   std::unique_ptr<ConnectionFileDescriptor> conn_ap(
240       new ConnectionFileDescriptor());
241   if (conn_ap.get()) {
242     // Only try once for now.
243     // TODO: check if we should be retrying?
244     const uint32_t max_retry_count = 1;
245     for (uint32_t retry_count = 0; retry_count < max_retry_count;
246          ++retry_count) {
247       if (conn_ap->Connect(remote_url, &error) == eConnectionStatusSuccess)
248         break;
249       usleep(100000);
250     }
251   }
252 
253   if (conn_ap->IsConnected()) {
254     const TCPSocket &socket =
255         static_cast<const TCPSocket &>(*conn_ap->GetReadObject());
256     const uint16_t reply_port = socket.GetLocalPortNumber();
257 
258     if (reply_port != 0) {
259       m_comm.SetConnection(conn_ap.release());
260 
261       if (m_comm.SendRequestReattach(reply_port)) {
262         if (m_comm.SendRequestConnect(reply_port, reply_port,
263                                       "Greetings from LLDB...")) {
264           m_comm.GetVersion();
265 
266           Target &target = GetTarget();
267           ArchSpec kernel_arch;
268           // The host architecture
269           GetHostArchitecture(kernel_arch);
270           ArchSpec target_arch = target.GetArchitecture();
271           // Merge in any unspecified stuff into the target architecture in
272           // case the target arch isn't set at all or incompletely.
273           target_arch.MergeFrom(kernel_arch);
274           target.SetArchitecture(target_arch);
275 
276           /* Get the kernel's UUID and load address via KDP_KERNELVERSION
277            * packet.  */
278           /* An EFI kdp session has neither UUID nor load address. */
279 
280           UUID kernel_uuid = m_comm.GetUUID();
281           addr_t kernel_load_addr = m_comm.GetLoadAddress();
282 
283           if (m_comm.RemoteIsEFI()) {
284             // Select an invalid plugin name for the dynamic loader so one
285             // doesn't get used since EFI does its own manual loading via
286             // python scripting
287             static ConstString g_none_dynamic_loader("none");
288             m_dyld_plugin_name = g_none_dynamic_loader;
289 
290             if (kernel_uuid.IsValid()) {
291               // If EFI passed in a UUID= try to lookup UUID The slide will not
292               // be provided. But the UUID lookup will be used to launch EFI
293               // debug scripts from the dSYM, that can load all of the symbols.
294               ModuleSpec module_spec;
295               module_spec.GetUUID() = kernel_uuid;
296               module_spec.GetArchitecture() = target.GetArchitecture();
297 
298               // Lookup UUID locally, before attempting dsymForUUID like action
299               module_spec.GetSymbolFileSpec() =
300                   Symbols::LocateExecutableSymbolFile(module_spec);
301               if (module_spec.GetSymbolFileSpec()) {
302                 ModuleSpec executable_module_spec =
303                     Symbols::LocateExecutableObjectFile(module_spec);
304                 if (executable_module_spec.GetFileSpec().Exists()) {
305                   module_spec.GetFileSpec() =
306                       executable_module_spec.GetFileSpec();
307                 }
308               }
309               if (!module_spec.GetSymbolFileSpec() ||
310                   !module_spec.GetSymbolFileSpec())
311                 Symbols::DownloadObjectAndSymbolFile(module_spec, true);
312 
313               if (module_spec.GetFileSpec().Exists()) {
314                 ModuleSP module_sp(new Module(module_spec));
315                 if (module_sp.get() && module_sp->GetObjectFile()) {
316                   // Get the current target executable
317                   ModuleSP exe_module_sp(target.GetExecutableModule());
318 
319                   // Make sure you don't already have the right module loaded
320                   // and they will be uniqued
321                   if (exe_module_sp.get() != module_sp.get())
322                     target.SetExecutableModule(module_sp, eLoadDependentsNo);
323                 }
324               }
325             }
326           } else if (m_comm.RemoteIsDarwinKernel()) {
327             m_dyld_plugin_name =
328                 DynamicLoaderDarwinKernel::GetPluginNameStatic();
329             if (kernel_load_addr != LLDB_INVALID_ADDRESS) {
330               m_kernel_load_addr = kernel_load_addr;
331             }
332           }
333 
334           // Set the thread ID
335           UpdateThreadListIfNeeded();
336           SetID(1);
337           GetThreadList();
338           SetPrivateState(eStateStopped);
339           StreamSP async_strm_sp(target.GetDebugger().GetAsyncOutputStream());
340           if (async_strm_sp) {
341             const char *cstr;
342             if ((cstr = m_comm.GetKernelVersion()) != NULL) {
343               async_strm_sp->Printf("Version: %s\n", cstr);
344               async_strm_sp->Flush();
345             }
346             //                      if ((cstr = m_comm.GetImagePath ()) != NULL)
347             //                      {
348             //                          async_strm_sp->Printf ("Image Path:
349             //                          %s\n", cstr);
350             //                          async_strm_sp->Flush();
351             //                      }
352           }
353         } else {
354           error.SetErrorString("KDP_REATTACH failed");
355         }
356       } else {
357         error.SetErrorString("KDP_REATTACH failed");
358       }
359     } else {
360       error.SetErrorString("invalid reply port from UDP connection");
361     }
362   } else {
363     if (error.Success())
364       error.SetErrorStringWithFormat("failed to connect to '%s'",
365                                      remote_url.str().c_str());
366   }
367   if (error.Fail())
368     m_comm.Disconnect();
369 
370   return error;
371 }
372 
373 //----------------------------------------------------------------------
374 // Process Control
375 //----------------------------------------------------------------------
376 Status ProcessKDP::DoLaunch(Module *exe_module,
377                             ProcessLaunchInfo &launch_info) {
378   Status error;
379   error.SetErrorString("launching not supported in kdp-remote plug-in");
380   return error;
381 }
382 
383 Status
384 ProcessKDP::DoAttachToProcessWithID(lldb::pid_t attach_pid,
385                                     const ProcessAttachInfo &attach_info) {
386   Status error;
387   error.SetErrorString(
388       "attach to process by ID is not supported in kdp remote debugging");
389   return error;
390 }
391 
392 Status
393 ProcessKDP::DoAttachToProcessWithName(const char *process_name,
394                                       const ProcessAttachInfo &attach_info) {
395   Status error;
396   error.SetErrorString(
397       "attach to process by name is not supported in kdp remote debugging");
398   return error;
399 }
400 
401 void ProcessKDP::DidAttach(ArchSpec &process_arch) {
402   Process::DidAttach(process_arch);
403 
404   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_PROCESS));
405   if (log)
406     log->Printf("ProcessKDP::DidAttach()");
407   if (GetID() != LLDB_INVALID_PROCESS_ID) {
408     GetHostArchitecture(process_arch);
409   }
410 }
411 
412 addr_t ProcessKDP::GetImageInfoAddress() { return m_kernel_load_addr; }
413 
414 lldb_private::DynamicLoader *ProcessKDP::GetDynamicLoader() {
415   if (m_dyld_ap.get() == NULL)
416     m_dyld_ap.reset(DynamicLoader::FindPlugin(
417         this,
418         m_dyld_plugin_name.IsEmpty() ? NULL : m_dyld_plugin_name.GetCString()));
419   return m_dyld_ap.get();
420 }
421 
422 Status ProcessKDP::WillResume() { return Status(); }
423 
424 Status ProcessKDP::DoResume() {
425   Status error;
426   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_PROCESS));
427   // Only start the async thread if we try to do any process control
428   if (!m_async_thread.IsJoinable())
429     StartAsyncThread();
430 
431   bool resume = false;
432 
433   // With KDP there is only one thread we can tell what to do
434   ThreadSP kernel_thread_sp(m_thread_list.FindThreadByProtocolID(g_kernel_tid));
435 
436   if (kernel_thread_sp) {
437     const StateType thread_resume_state =
438         kernel_thread_sp->GetTemporaryResumeState();
439 
440     if (log)
441       log->Printf("ProcessKDP::DoResume() thread_resume_state = %s",
442                   StateAsCString(thread_resume_state));
443     switch (thread_resume_state) {
444     case eStateSuspended:
445       // Nothing to do here when a thread will stay suspended we just leave the
446       // CPU mask bit set to zero for the thread
447       if (log)
448         log->Printf("ProcessKDP::DoResume() = suspended???");
449       break;
450 
451     case eStateStepping: {
452       lldb::RegisterContextSP reg_ctx_sp(
453           kernel_thread_sp->GetRegisterContext());
454 
455       if (reg_ctx_sp) {
456         if (log)
457           log->Printf(
458               "ProcessKDP::DoResume () reg_ctx_sp->HardwareSingleStep (true);");
459         reg_ctx_sp->HardwareSingleStep(true);
460         resume = true;
461       } else {
462         error.SetErrorStringWithFormat(
463             "KDP thread 0x%llx has no register context",
464             kernel_thread_sp->GetID());
465       }
466     } break;
467 
468     case eStateRunning: {
469       lldb::RegisterContextSP reg_ctx_sp(
470           kernel_thread_sp->GetRegisterContext());
471 
472       if (reg_ctx_sp) {
473         if (log)
474           log->Printf("ProcessKDP::DoResume () reg_ctx_sp->HardwareSingleStep "
475                       "(false);");
476         reg_ctx_sp->HardwareSingleStep(false);
477         resume = true;
478       } else {
479         error.SetErrorStringWithFormat(
480             "KDP thread 0x%llx has no register context",
481             kernel_thread_sp->GetID());
482       }
483     } break;
484 
485     default:
486       // The only valid thread resume states are listed above
487       llvm_unreachable("invalid thread resume state");
488     }
489   }
490 
491   if (resume) {
492     if (log)
493       log->Printf("ProcessKDP::DoResume () sending resume");
494 
495     if (m_comm.SendRequestResume()) {
496       m_async_broadcaster.BroadcastEvent(eBroadcastBitAsyncContinue);
497       SetPrivateState(eStateRunning);
498     } else
499       error.SetErrorString("KDP resume failed");
500   } else {
501     error.SetErrorString("kernel thread is suspended");
502   }
503 
504   return error;
505 }
506 
507 lldb::ThreadSP ProcessKDP::GetKernelThread() {
508   // KDP only tells us about one thread/core. Any other threads will usually
509   // be the ones that are read from memory by the OS plug-ins.
510 
511   ThreadSP thread_sp(m_kernel_thread_wp.lock());
512   if (!thread_sp) {
513     thread_sp.reset(new ThreadKDP(*this, g_kernel_tid));
514     m_kernel_thread_wp = thread_sp;
515   }
516   return thread_sp;
517 }
518 
519 bool ProcessKDP::UpdateThreadList(ThreadList &old_thread_list,
520                                   ThreadList &new_thread_list) {
521   // locker will keep a mutex locked until it goes out of scope
522   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_THREAD));
523   LLDB_LOGV(log, "pid = {0}", GetID());
524 
525   // Even though there is a CPU mask, it doesn't mean we can see each CPU
526   // individually, there is really only one. Lets call this thread 1.
527   ThreadSP thread_sp(
528       old_thread_list.FindThreadByProtocolID(g_kernel_tid, false));
529   if (!thread_sp)
530     thread_sp = GetKernelThread();
531   new_thread_list.AddThread(thread_sp);
532 
533   return new_thread_list.GetSize(false) > 0;
534 }
535 
536 void ProcessKDP::RefreshStateAfterStop() {
537   // Let all threads recover from stopping and do any clean up based on the
538   // previous thread state (if any).
539   m_thread_list.RefreshStateAfterStop();
540 }
541 
542 Status ProcessKDP::DoHalt(bool &caused_stop) {
543   Status error;
544 
545   if (m_comm.IsRunning()) {
546     if (m_destroy_in_process) {
547       // If we are attempting to destroy, we need to not return an error to Halt
548       // or DoDestroy won't get called. We are also currently running, so send
549       // a process stopped event
550       SetPrivateState(eStateStopped);
551     } else {
552       error.SetErrorString("KDP cannot interrupt a running kernel");
553     }
554   }
555   return error;
556 }
557 
558 Status ProcessKDP::DoDetach(bool keep_stopped) {
559   Status error;
560   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_PROCESS));
561   if (log)
562     log->Printf("ProcessKDP::DoDetach(keep_stopped = %i)", keep_stopped);
563 
564   if (m_comm.IsRunning()) {
565     // We are running and we can't interrupt a running kernel, so we need to
566     // just close the connection to the kernel and hope for the best
567   } else {
568     // If we are going to keep the target stopped, then don't send the
569     // disconnect message.
570     if (!keep_stopped && m_comm.IsConnected()) {
571       const bool success = m_comm.SendRequestDisconnect();
572       if (log) {
573         if (success)
574           log->PutCString(
575               "ProcessKDP::DoDetach() detach packet sent successfully");
576         else
577           log->PutCString(
578               "ProcessKDP::DoDetach() connection channel shutdown failed");
579       }
580       m_comm.Disconnect();
581     }
582   }
583   StopAsyncThread();
584   m_comm.Clear();
585 
586   SetPrivateState(eStateDetached);
587   ResumePrivateStateThread();
588 
589   // KillDebugserverProcess ();
590   return error;
591 }
592 
593 Status ProcessKDP::DoDestroy() {
594   // For KDP there really is no difference between destroy and detach
595   bool keep_stopped = false;
596   return DoDetach(keep_stopped);
597 }
598 
599 //------------------------------------------------------------------
600 // Process Queries
601 //------------------------------------------------------------------
602 
603 bool ProcessKDP::IsAlive() {
604   return m_comm.IsConnected() && Process::IsAlive();
605 }
606 
607 //------------------------------------------------------------------
608 // Process Memory
609 //------------------------------------------------------------------
610 size_t ProcessKDP::DoReadMemory(addr_t addr, void *buf, size_t size,
611                                 Status &error) {
612   uint8_t *data_buffer = (uint8_t *)buf;
613   if (m_comm.IsConnected()) {
614     const size_t max_read_size = 512;
615     size_t total_bytes_read = 0;
616 
617     // Read the requested amount of memory in 512 byte chunks
618     while (total_bytes_read < size) {
619       size_t bytes_to_read_this_request = size - total_bytes_read;
620       if (bytes_to_read_this_request > max_read_size) {
621         bytes_to_read_this_request = max_read_size;
622       }
623       size_t bytes_read = m_comm.SendRequestReadMemory(
624           addr + total_bytes_read, data_buffer + total_bytes_read,
625           bytes_to_read_this_request, error);
626       total_bytes_read += bytes_read;
627       if (error.Fail() || bytes_read == 0) {
628         return total_bytes_read;
629       }
630     }
631 
632     return total_bytes_read;
633   }
634   error.SetErrorString("not connected");
635   return 0;
636 }
637 
638 size_t ProcessKDP::DoWriteMemory(addr_t addr, const void *buf, size_t size,
639                                  Status &error) {
640   if (m_comm.IsConnected())
641     return m_comm.SendRequestWriteMemory(addr, buf, size, error);
642   error.SetErrorString("not connected");
643   return 0;
644 }
645 
646 lldb::addr_t ProcessKDP::DoAllocateMemory(size_t size, uint32_t permissions,
647                                           Status &error) {
648   error.SetErrorString(
649       "memory allocation not supported in kdp remote debugging");
650   return LLDB_INVALID_ADDRESS;
651 }
652 
653 Status ProcessKDP::DoDeallocateMemory(lldb::addr_t addr) {
654   Status error;
655   error.SetErrorString(
656       "memory deallocation not supported in kdp remote debugging");
657   return error;
658 }
659 
660 Status ProcessKDP::EnableBreakpointSite(BreakpointSite *bp_site) {
661   if (m_comm.LocalBreakpointsAreSupported()) {
662     Status error;
663     if (!bp_site->IsEnabled()) {
664       if (m_comm.SendRequestBreakpoint(true, bp_site->GetLoadAddress())) {
665         bp_site->SetEnabled(true);
666         bp_site->SetType(BreakpointSite::eExternal);
667       } else {
668         error.SetErrorString("KDP set breakpoint failed");
669       }
670     }
671     return error;
672   }
673   return EnableSoftwareBreakpoint(bp_site);
674 }
675 
676 Status ProcessKDP::DisableBreakpointSite(BreakpointSite *bp_site) {
677   if (m_comm.LocalBreakpointsAreSupported()) {
678     Status error;
679     if (bp_site->IsEnabled()) {
680       BreakpointSite::Type bp_type = bp_site->GetType();
681       if (bp_type == BreakpointSite::eExternal) {
682         if (m_destroy_in_process && m_comm.IsRunning()) {
683           // We are trying to destroy our connection and we are running
684           bp_site->SetEnabled(false);
685         } else {
686           if (m_comm.SendRequestBreakpoint(false, bp_site->GetLoadAddress()))
687             bp_site->SetEnabled(false);
688           else
689             error.SetErrorString("KDP remove breakpoint failed");
690         }
691       } else {
692         error = DisableSoftwareBreakpoint(bp_site);
693       }
694     }
695     return error;
696   }
697   return DisableSoftwareBreakpoint(bp_site);
698 }
699 
700 Status ProcessKDP::EnableWatchpoint(Watchpoint *wp, bool notify) {
701   Status error;
702   error.SetErrorString(
703       "watchpoints are not supported in kdp remote debugging");
704   return error;
705 }
706 
707 Status ProcessKDP::DisableWatchpoint(Watchpoint *wp, bool notify) {
708   Status error;
709   error.SetErrorString(
710       "watchpoints are not supported in kdp remote debugging");
711   return error;
712 }
713 
714 void ProcessKDP::Clear() { m_thread_list.Clear(); }
715 
716 Status ProcessKDP::DoSignal(int signo) {
717   Status error;
718   error.SetErrorString(
719       "sending signals is not supported in kdp remote debugging");
720   return error;
721 }
722 
723 void ProcessKDP::Initialize() {
724   static llvm::once_flag g_once_flag;
725 
726   llvm::call_once(g_once_flag, []() {
727     PluginManager::RegisterPlugin(GetPluginNameStatic(),
728                                   GetPluginDescriptionStatic(), CreateInstance,
729                                   DebuggerInitialize);
730 
731     ProcessKDPLog::Initialize();
732   });
733 }
734 
735 void ProcessKDP::DebuggerInitialize(lldb_private::Debugger &debugger) {
736   if (!PluginManager::GetSettingForProcessPlugin(
737           debugger, PluginProperties::GetSettingName())) {
738     const bool is_global_setting = true;
739     PluginManager::CreateSettingForProcessPlugin(
740         debugger, GetGlobalPluginProperties()->GetValueProperties(),
741         ConstString("Properties for the kdp-remote process plug-in."),
742         is_global_setting);
743   }
744 }
745 
746 bool ProcessKDP::StartAsyncThread() {
747   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_PROCESS));
748 
749   if (log)
750     log->Printf("ProcessKDP::StartAsyncThread ()");
751 
752   if (m_async_thread.IsJoinable())
753     return true;
754 
755   m_async_thread = ThreadLauncher::LaunchThread(
756       "<lldb.process.kdp-remote.async>", ProcessKDP::AsyncThread, this, NULL);
757   return m_async_thread.IsJoinable();
758 }
759 
760 void ProcessKDP::StopAsyncThread() {
761   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_PROCESS));
762 
763   if (log)
764     log->Printf("ProcessKDP::StopAsyncThread ()");
765 
766   m_async_broadcaster.BroadcastEvent(eBroadcastBitAsyncThreadShouldExit);
767 
768   // Stop the stdio thread
769   if (m_async_thread.IsJoinable())
770     m_async_thread.Join(nullptr);
771 }
772 
773 void *ProcessKDP::AsyncThread(void *arg) {
774   ProcessKDP *process = (ProcessKDP *)arg;
775 
776   const lldb::pid_t pid = process->GetID();
777 
778   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_PROCESS));
779   if (log)
780     log->Printf("ProcessKDP::AsyncThread (arg = %p, pid = %" PRIu64
781                 ") thread starting...",
782                 arg, pid);
783 
784   ListenerSP listener_sp(Listener::MakeListener("ProcessKDP::AsyncThread"));
785   EventSP event_sp;
786   const uint32_t desired_event_mask =
787       eBroadcastBitAsyncContinue | eBroadcastBitAsyncThreadShouldExit;
788 
789   if (listener_sp->StartListeningForEvents(&process->m_async_broadcaster,
790                                            desired_event_mask) ==
791       desired_event_mask) {
792     bool done = false;
793     while (!done) {
794       if (log)
795         log->Printf("ProcessKDP::AsyncThread (pid = %" PRIu64
796                     ") listener.WaitForEvent (NULL, event_sp)...",
797                     pid);
798       if (listener_sp->GetEvent(event_sp, llvm::None)) {
799         uint32_t event_type = event_sp->GetType();
800         if (log)
801           log->Printf("ProcessKDP::AsyncThread (pid = %" PRIu64
802                       ") Got an event of type: %d...",
803                       pid, event_type);
804 
805         // When we are running, poll for 1 second to try and get an exception
806         // to indicate the process has stopped. If we don't get one, check to
807         // make sure no one asked us to exit
808         bool is_running = false;
809         DataExtractor exc_reply_packet;
810         do {
811           switch (event_type) {
812           case eBroadcastBitAsyncContinue: {
813             is_running = true;
814             if (process->m_comm.WaitForPacketWithTimeoutMicroSeconds(
815                     exc_reply_packet, 1 * USEC_PER_SEC)) {
816               ThreadSP thread_sp(process->GetKernelThread());
817               if (thread_sp) {
818                 lldb::RegisterContextSP reg_ctx_sp(
819                     thread_sp->GetRegisterContext());
820                 if (reg_ctx_sp)
821                   reg_ctx_sp->InvalidateAllRegisters();
822                 static_cast<ThreadKDP *>(thread_sp.get())
823                     ->SetStopInfoFrom_KDP_EXCEPTION(exc_reply_packet);
824               }
825 
826               // TODO: parse the stop reply packet
827               is_running = false;
828               process->SetPrivateState(eStateStopped);
829             } else {
830               // Check to see if we are supposed to exit. There is no way to
831               // interrupt a running kernel, so all we can do is wait for an
832               // exception or detach...
833               if (listener_sp->GetEvent(event_sp,
834                                         std::chrono::microseconds(0))) {
835                 // We got an event, go through the loop again
836                 event_type = event_sp->GetType();
837               }
838             }
839           } break;
840 
841           case eBroadcastBitAsyncThreadShouldExit:
842             if (log)
843               log->Printf("ProcessKDP::AsyncThread (pid = %" PRIu64
844                           ") got eBroadcastBitAsyncThreadShouldExit...",
845                           pid);
846             done = true;
847             is_running = false;
848             break;
849 
850           default:
851             if (log)
852               log->Printf("ProcessKDP::AsyncThread (pid = %" PRIu64
853                           ") got unknown event 0x%8.8x",
854                           pid, event_type);
855             done = true;
856             is_running = false;
857             break;
858           }
859         } while (is_running);
860       } else {
861         if (log)
862           log->Printf("ProcessKDP::AsyncThread (pid = %" PRIu64
863                       ") listener.WaitForEvent (NULL, event_sp) => false",
864                       pid);
865         done = true;
866       }
867     }
868   }
869 
870   if (log)
871     log->Printf("ProcessKDP::AsyncThread (arg = %p, pid = %" PRIu64
872                 ") thread exiting...",
873                 arg, pid);
874 
875   process->m_async_thread.Reset();
876   return NULL;
877 }
878 
879 class CommandObjectProcessKDPPacketSend : public CommandObjectParsed {
880 private:
881   OptionGroupOptions m_option_group;
882   OptionGroupUInt64 m_command_byte;
883   OptionGroupString m_packet_data;
884 
885   virtual Options *GetOptions() { return &m_option_group; }
886 
887 public:
888   CommandObjectProcessKDPPacketSend(CommandInterpreter &interpreter)
889       : CommandObjectParsed(interpreter, "process plugin packet send",
890                             "Send a custom packet through the KDP protocol by "
891                             "specifying the command byte and the packet "
892                             "payload data. A packet will be sent with a "
893                             "correct header and payload, and the raw result "
894                             "bytes will be displayed as a string value. ",
895                             NULL),
896         m_option_group(),
897         m_command_byte(LLDB_OPT_SET_1, true, "command", 'c', 0, eArgTypeNone,
898                        "Specify the command byte to use when sending the KDP "
899                        "request packet.",
900                        0),
901         m_packet_data(LLDB_OPT_SET_1, false, "payload", 'p', 0, eArgTypeNone,
902                       "Specify packet payload bytes as a hex ASCII string with "
903                       "no spaces or hex prefixes.",
904                       NULL) {
905     m_option_group.Append(&m_command_byte, LLDB_OPT_SET_ALL, LLDB_OPT_SET_1);
906     m_option_group.Append(&m_packet_data, LLDB_OPT_SET_ALL, LLDB_OPT_SET_1);
907     m_option_group.Finalize();
908   }
909 
910   ~CommandObjectProcessKDPPacketSend() {}
911 
912   bool DoExecute(Args &command, CommandReturnObject &result) {
913     const size_t argc = command.GetArgumentCount();
914     if (argc == 0) {
915       if (!m_command_byte.GetOptionValue().OptionWasSet()) {
916         result.AppendError(
917             "the --command option must be set to a valid command byte");
918         result.SetStatus(eReturnStatusFailed);
919       } else {
920         const uint64_t command_byte =
921             m_command_byte.GetOptionValue().GetUInt64Value(0);
922         if (command_byte > 0 && command_byte <= UINT8_MAX) {
923           ProcessKDP *process =
924               (ProcessKDP *)m_interpreter.GetExecutionContext().GetProcessPtr();
925           if (process) {
926             const StateType state = process->GetState();
927 
928             if (StateIsStoppedState(state, true)) {
929               std::vector<uint8_t> payload_bytes;
930               const char *ascii_hex_bytes_cstr =
931                   m_packet_data.GetOptionValue().GetCurrentValue();
932               if (ascii_hex_bytes_cstr && ascii_hex_bytes_cstr[0]) {
933                 StringExtractor extractor(ascii_hex_bytes_cstr);
934                 const size_t ascii_hex_bytes_cstr_len =
935                     extractor.GetStringRef().size();
936                 if (ascii_hex_bytes_cstr_len & 1) {
937                   result.AppendErrorWithFormat("payload data must contain an "
938                                                "even number of ASCII hex "
939                                                "characters: '%s'",
940                                                ascii_hex_bytes_cstr);
941                   result.SetStatus(eReturnStatusFailed);
942                   return false;
943                 }
944                 payload_bytes.resize(ascii_hex_bytes_cstr_len / 2);
945                 if (extractor.GetHexBytes(payload_bytes, '\xdd') !=
946                     payload_bytes.size()) {
947                   result.AppendErrorWithFormat("payload data must only contain "
948                                                "ASCII hex characters (no "
949                                                "spaces or hex prefixes): '%s'",
950                                                ascii_hex_bytes_cstr);
951                   result.SetStatus(eReturnStatusFailed);
952                   return false;
953                 }
954               }
955               Status error;
956               DataExtractor reply;
957               process->GetCommunication().SendRawRequest(
958                   command_byte,
959                   payload_bytes.empty() ? NULL : payload_bytes.data(),
960                   payload_bytes.size(), reply, error);
961 
962               if (error.Success()) {
963                 // Copy the binary bytes into a hex ASCII string for the result
964                 StreamString packet;
965                 packet.PutBytesAsRawHex8(
966                     reply.GetDataStart(), reply.GetByteSize(),
967                     endian::InlHostByteOrder(), endian::InlHostByteOrder());
968                 result.AppendMessage(packet.GetString());
969                 result.SetStatus(eReturnStatusSuccessFinishResult);
970                 return true;
971               } else {
972                 const char *error_cstr = error.AsCString();
973                 if (error_cstr && error_cstr[0])
974                   result.AppendError(error_cstr);
975                 else
976                   result.AppendErrorWithFormat("unknown error 0x%8.8x",
977                                                error.GetError());
978                 result.SetStatus(eReturnStatusFailed);
979                 return false;
980               }
981             } else {
982               result.AppendErrorWithFormat("process must be stopped in order "
983                                            "to send KDP packets, state is %s",
984                                            StateAsCString(state));
985               result.SetStatus(eReturnStatusFailed);
986             }
987           } else {
988             result.AppendError("invalid process");
989             result.SetStatus(eReturnStatusFailed);
990           }
991         } else {
992           result.AppendErrorWithFormat("invalid command byte 0x%" PRIx64
993                                        ", valid values are 1 - 255",
994                                        command_byte);
995           result.SetStatus(eReturnStatusFailed);
996         }
997       }
998     } else {
999       result.AppendErrorWithFormat("'%s' takes no arguments, only options.",
1000                                    m_cmd_name.c_str());
1001       result.SetStatus(eReturnStatusFailed);
1002     }
1003     return false;
1004   }
1005 };
1006 
1007 class CommandObjectProcessKDPPacket : public CommandObjectMultiword {
1008 private:
1009 public:
1010   CommandObjectProcessKDPPacket(CommandInterpreter &interpreter)
1011       : CommandObjectMultiword(interpreter, "process plugin packet",
1012                                "Commands that deal with KDP remote packets.",
1013                                NULL) {
1014     LoadSubCommand(
1015         "send",
1016         CommandObjectSP(new CommandObjectProcessKDPPacketSend(interpreter)));
1017   }
1018 
1019   ~CommandObjectProcessKDPPacket() {}
1020 };
1021 
1022 class CommandObjectMultiwordProcessKDP : public CommandObjectMultiword {
1023 public:
1024   CommandObjectMultiwordProcessKDP(CommandInterpreter &interpreter)
1025       : CommandObjectMultiword(
1026             interpreter, "process plugin",
1027             "Commands for operating on a ProcessKDP process.",
1028             "process plugin <subcommand> [<subcommand-options>]") {
1029     LoadSubCommand("packet", CommandObjectSP(new CommandObjectProcessKDPPacket(
1030                                  interpreter)));
1031   }
1032 
1033   ~CommandObjectMultiwordProcessKDP() {}
1034 };
1035 
1036 CommandObject *ProcessKDP::GetPluginCommandObject() {
1037   if (!m_command_sp)
1038     m_command_sp.reset(new CommandObjectMultiwordProcessKDP(
1039         GetTarget().GetDebugger().GetCommandInterpreter()));
1040   return m_command_sp.get();
1041 }
1042