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/Core/State.h"
23 #include "lldb/Utility/UUID.h"
24 #include "lldb/Host/ConnectionFileDescriptor.h"
25 #include "lldb/Host/Host.h"
26 #include "lldb/Host/Symbols.h"
27 #include "lldb/Host/ThreadLauncher.h"
28 #include "lldb/Host/common/TCPSocket.h"
29 #include "lldb/Interpreter/CommandInterpreter.h"
30 #include "lldb/Interpreter/CommandObject.h"
31 #include "lldb/Interpreter/CommandObjectMultiword.h"
32 #include "lldb/Interpreter/CommandReturnObject.h"
33 #include "lldb/Interpreter/OptionGroupString.h"
34 #include "lldb/Interpreter/OptionGroupUInt64.h"
35 #include "lldb/Interpreter/OptionValueProperties.h"
36 #include "lldb/Symbol/ObjectFile.h"
37 #include "lldb/Target/RegisterContext.h"
38 #include "lldb/Target/Target.h"
39 #include "lldb/Target/Thread.h"
40 #include "lldb/Utility/StringExtractor.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
176   // to make sure all of the broadcaster cleanup goes as planned. If we
177   // destruct this class, then Process::~Process() might have problems
178   // trying to fully 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
230   // memory and we don't want to be mucking with threads that might
231   // already be handling 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
286             // since EFI does its own manual loading via 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
292               // The slide will not be provided. But the UUID
293               // lookup will be used to launch EFI debug scripts
294               // from the dSYM, that can load all of the symbols.
295               ModuleSpec module_spec;
296               module_spec.GetUUID() = kernel_uuid;
297               module_spec.GetArchitecture() = target.GetArchitecture();
298 
299               // Lookup UUID locally, before attempting dsymForUUID like action
300               module_spec.GetSymbolFileSpec() =
301                   Symbols::LocateExecutableSymbolFile(module_spec);
302               if (module_spec.GetSymbolFileSpec()) {
303                 ModuleSpec executable_module_spec =
304                     Symbols::LocateExecutableObjectFile(module_spec);
305                 if (executable_module_spec.GetFileSpec().Exists()) {
306                   module_spec.GetFileSpec() =
307                       executable_module_spec.GetFileSpec();
308                 }
309               }
310               if (!module_spec.GetSymbolFileSpec() ||
311                   !module_spec.GetSymbolFileSpec())
312                 Symbols::DownloadObjectAndSymbolFile(module_spec, true);
313 
314               if (module_spec.GetFileSpec().Exists()) {
315                 ModuleSP module_sp(new Module(module_spec));
316                 if (module_sp.get() && module_sp->GetObjectFile()) {
317                   // Get the current target executable
318                   ModuleSP exe_module_sp(target.GetExecutableModule());
319 
320                   // Make sure you don't already have the right module loaded
321                   // and they will be uniqued
322                   if (exe_module_sp.get() != module_sp.get())
323                     target.SetExecutableModule(module_sp, false);
324                 }
325               }
326             }
327           } else if (m_comm.RemoteIsDarwinKernel()) {
328             m_dyld_plugin_name =
329                 DynamicLoaderDarwinKernel::GetPluginNameStatic();
330             if (kernel_load_addr != LLDB_INVALID_ADDRESS) {
331               m_kernel_load_addr = kernel_load_addr;
332             }
333           }
334 
335           // Set the thread ID
336           UpdateThreadListIfNeeded();
337           SetID(1);
338           GetThreadList();
339           SetPrivateState(eStateStopped);
340           StreamSP async_strm_sp(target.GetDebugger().GetAsyncOutputStream());
341           if (async_strm_sp) {
342             const char *cstr;
343             if ((cstr = m_comm.GetKernelVersion()) != NULL) {
344               async_strm_sp->Printf("Version: %s\n", cstr);
345               async_strm_sp->Flush();
346             }
347             //                      if ((cstr = m_comm.GetImagePath ()) != NULL)
348             //                      {
349             //                          async_strm_sp->Printf ("Image Path:
350             //                          %s\n", cstr);
351             //                          async_strm_sp->Flush();
352             //                      }
353           }
354         } else {
355           error.SetErrorString("KDP_REATTACH failed");
356         }
357       } else {
358         error.SetErrorString("KDP_REATTACH failed");
359       }
360     } else {
361       error.SetErrorString("invalid reply port from UDP connection");
362     }
363   } else {
364     if (error.Success())
365       error.SetErrorStringWithFormat("failed to connect to '%s'",
366                                      remote_url.str().c_str());
367   }
368   if (error.Fail())
369     m_comm.Disconnect();
370 
371   return error;
372 }
373 
374 //----------------------------------------------------------------------
375 // Process Control
376 //----------------------------------------------------------------------
377 Status ProcessKDP::DoLaunch(Module *exe_module,
378                             ProcessLaunchInfo &launch_info) {
379   Status error;
380   error.SetErrorString("launching not supported in kdp-remote plug-in");
381   return error;
382 }
383 
384 Status
385 ProcessKDP::DoAttachToProcessWithID(lldb::pid_t attach_pid,
386                                     const ProcessAttachInfo &attach_info) {
387   Status error;
388   error.SetErrorString(
389       "attach to process by ID is not suppported in kdp remote debugging");
390   return error;
391 }
392 
393 Status
394 ProcessKDP::DoAttachToProcessWithName(const char *process_name,
395                                       const ProcessAttachInfo &attach_info) {
396   Status error;
397   error.SetErrorString(
398       "attach to process by name is not suppported in kdp remote debugging");
399   return error;
400 }
401 
402 void ProcessKDP::DidAttach(ArchSpec &process_arch) {
403   Process::DidAttach(process_arch);
404 
405   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_PROCESS));
406   if (log)
407     log->Printf("ProcessKDP::DidAttach()");
408   if (GetID() != LLDB_INVALID_PROCESS_ID) {
409     GetHostArchitecture(process_arch);
410   }
411 }
412 
413 addr_t ProcessKDP::GetImageInfoAddress() { return m_kernel_load_addr; }
414 
415 lldb_private::DynamicLoader *ProcessKDP::GetDynamicLoader() {
416   if (m_dyld_ap.get() == NULL)
417     m_dyld_ap.reset(DynamicLoader::FindPlugin(
418         this,
419         m_dyld_plugin_name.IsEmpty() ? NULL : m_dyld_plugin_name.GetCString()));
420   return m_dyld_ap.get();
421 }
422 
423 Status ProcessKDP::WillResume() { return Status(); }
424 
425 Status ProcessKDP::DoResume() {
426   Status error;
427   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_PROCESS));
428   // Only start the async thread if we try to do any process control
429   if (!m_async_thread.IsJoinable())
430     StartAsyncThread();
431 
432   bool resume = false;
433 
434   // With KDP there is only one thread we can tell what to do
435   ThreadSP kernel_thread_sp(m_thread_list.FindThreadByProtocolID(g_kernel_tid));
436 
437   if (kernel_thread_sp) {
438     const StateType thread_resume_state =
439         kernel_thread_sp->GetTemporaryResumeState();
440 
441     if (log)
442       log->Printf("ProcessKDP::DoResume() thread_resume_state = %s",
443                   StateAsCString(thread_resume_state));
444     switch (thread_resume_state) {
445     case eStateSuspended:
446       // Nothing to do here when a thread will stay suspended
447       // we just leave the CPU mask bit set to zero for the thread
448       if (log)
449         log->Printf("ProcessKDP::DoResume() = suspended???");
450       break;
451 
452     case eStateStepping: {
453       lldb::RegisterContextSP reg_ctx_sp(
454           kernel_thread_sp->GetRegisterContext());
455 
456       if (reg_ctx_sp) {
457         if (log)
458           log->Printf(
459               "ProcessKDP::DoResume () reg_ctx_sp->HardwareSingleStep (true);");
460         reg_ctx_sp->HardwareSingleStep(true);
461         resume = true;
462       } else {
463         error.SetErrorStringWithFormat(
464             "KDP thread 0x%llx has no register context",
465             kernel_thread_sp->GetID());
466       }
467     } break;
468 
469     case eStateRunning: {
470       lldb::RegisterContextSP reg_ctx_sp(
471           kernel_thread_sp->GetRegisterContext());
472 
473       if (reg_ctx_sp) {
474         if (log)
475           log->Printf("ProcessKDP::DoResume () reg_ctx_sp->HardwareSingleStep "
476                       "(false);");
477         reg_ctx_sp->HardwareSingleStep(false);
478         resume = true;
479       } else {
480         error.SetErrorStringWithFormat(
481             "KDP thread 0x%llx has no register context",
482             kernel_thread_sp->GetID());
483       }
484     } break;
485 
486     default:
487       // The only valid thread resume states are listed above
488       llvm_unreachable("invalid thread resume state");
489     }
490   }
491 
492   if (resume) {
493     if (log)
494       log->Printf("ProcessKDP::DoResume () sending resume");
495 
496     if (m_comm.SendRequestResume()) {
497       m_async_broadcaster.BroadcastEvent(eBroadcastBitAsyncContinue);
498       SetPrivateState(eStateRunning);
499     } else
500       error.SetErrorString("KDP resume failed");
501   } else {
502     error.SetErrorString("kernel thread is suspended");
503   }
504 
505   return error;
506 }
507 
508 lldb::ThreadSP ProcessKDP::GetKernelThread() {
509   // KDP only tells us about one thread/core. Any other threads will usually
510   // be the ones that are read from memory by the OS plug-ins.
511 
512   ThreadSP thread_sp(m_kernel_thread_wp.lock());
513   if (!thread_sp) {
514     thread_sp.reset(new ThreadKDP(*this, g_kernel_tid));
515     m_kernel_thread_wp = thread_sp;
516   }
517   return thread_sp;
518 }
519 
520 bool ProcessKDP::UpdateThreadList(ThreadList &old_thread_list,
521                                   ThreadList &new_thread_list) {
522   // locker will keep a mutex locked until it goes out of scope
523   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_THREAD));
524   LLDB_LOGV(log, "pid = {0}", GetID());
525 
526   // Even though there is a CPU mask, it doesn't mean we can see each CPU
527   // individually, there is really only one. Lets call this thread 1.
528   ThreadSP thread_sp(
529       old_thread_list.FindThreadByProtocolID(g_kernel_tid, false));
530   if (!thread_sp)
531     thread_sp = GetKernelThread();
532   new_thread_list.AddThread(thread_sp);
533 
534   return new_thread_list.GetSize(false) > 0;
535 }
536 
537 void ProcessKDP::RefreshStateAfterStop() {
538   // Let all threads recover from stopping and do any clean up based
539   // on the previous thread state (if any).
540   m_thread_list.RefreshStateAfterStop();
541 }
542 
543 Status ProcessKDP::DoHalt(bool &caused_stop) {
544   Status error;
545 
546   if (m_comm.IsRunning()) {
547     if (m_destroy_in_process) {
548       // If we are attemping to destroy, we need to not return an error to
549       // Halt or DoDestroy won't get called.
550       // We are also currently running, so send a process stopped event
551       SetPrivateState(eStateStopped);
552     } else {
553       error.SetErrorString("KDP cannot interrupt a running kernel");
554     }
555   }
556   return error;
557 }
558 
559 Status ProcessKDP::DoDetach(bool keep_stopped) {
560   Status error;
561   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_PROCESS));
562   if (log)
563     log->Printf("ProcessKDP::DoDetach(keep_stopped = %i)", keep_stopped);
564 
565   if (m_comm.IsRunning()) {
566     // We are running and we can't interrupt a running kernel, so we need
567     // to just close the connection to the kernel and hope for the best
568   } else {
569     // If we are going to keep the target stopped, then don't send the
570     // disconnect message.
571     if (!keep_stopped && m_comm.IsConnected()) {
572       const bool success = m_comm.SendRequestDisconnect();
573       if (log) {
574         if (success)
575           log->PutCString(
576               "ProcessKDP::DoDetach() detach packet sent successfully");
577         else
578           log->PutCString(
579               "ProcessKDP::DoDetach() connection channel shutdown failed");
580       }
581       m_comm.Disconnect();
582     }
583   }
584   StopAsyncThread();
585   m_comm.Clear();
586 
587   SetPrivateState(eStateDetached);
588   ResumePrivateStateThread();
589 
590   // KillDebugserverProcess ();
591   return error;
592 }
593 
594 Status ProcessKDP::DoDestroy() {
595   // For KDP there really is no difference between destroy and detach
596   bool keep_stopped = false;
597   return DoDetach(keep_stopped);
598 }
599 
600 //------------------------------------------------------------------
601 // Process Queries
602 //------------------------------------------------------------------
603 
604 bool ProcessKDP::IsAlive() {
605   return m_comm.IsConnected() && Process::IsAlive();
606 }
607 
608 //------------------------------------------------------------------
609 // Process Memory
610 //------------------------------------------------------------------
611 size_t ProcessKDP::DoReadMemory(addr_t addr, void *buf, size_t size,
612                                 Status &error) {
613   uint8_t *data_buffer = (uint8_t *)buf;
614   if (m_comm.IsConnected()) {
615     const size_t max_read_size = 512;
616     size_t total_bytes_read = 0;
617 
618     // Read the requested amount of memory in 512 byte chunks
619     while (total_bytes_read < size) {
620       size_t bytes_to_read_this_request = size - total_bytes_read;
621       if (bytes_to_read_this_request > max_read_size) {
622         bytes_to_read_this_request = max_read_size;
623       }
624       size_t bytes_read = m_comm.SendRequestReadMemory(
625           addr + total_bytes_read, data_buffer + total_bytes_read,
626           bytes_to_read_this_request, error);
627       total_bytes_read += bytes_read;
628       if (error.Fail() || bytes_read == 0) {
629         return total_bytes_read;
630       }
631     }
632 
633     return total_bytes_read;
634   }
635   error.SetErrorString("not connected");
636   return 0;
637 }
638 
639 size_t ProcessKDP::DoWriteMemory(addr_t addr, const void *buf, size_t size,
640                                  Status &error) {
641   if (m_comm.IsConnected())
642     return m_comm.SendRequestWriteMemory(addr, buf, size, error);
643   error.SetErrorString("not connected");
644   return 0;
645 }
646 
647 lldb::addr_t ProcessKDP::DoAllocateMemory(size_t size, uint32_t permissions,
648                                           Status &error) {
649   error.SetErrorString(
650       "memory allocation not suppported in kdp remote debugging");
651   return LLDB_INVALID_ADDRESS;
652 }
653 
654 Status ProcessKDP::DoDeallocateMemory(lldb::addr_t addr) {
655   Status error;
656   error.SetErrorString(
657       "memory deallocation not suppported in kdp remote debugging");
658   return error;
659 }
660 
661 Status ProcessKDP::EnableBreakpointSite(BreakpointSite *bp_site) {
662   if (m_comm.LocalBreakpointsAreSupported()) {
663     Status error;
664     if (!bp_site->IsEnabled()) {
665       if (m_comm.SendRequestBreakpoint(true, bp_site->GetLoadAddress())) {
666         bp_site->SetEnabled(true);
667         bp_site->SetType(BreakpointSite::eExternal);
668       } else {
669         error.SetErrorString("KDP set breakpoint failed");
670       }
671     }
672     return error;
673   }
674   return EnableSoftwareBreakpoint(bp_site);
675 }
676 
677 Status ProcessKDP::DisableBreakpointSite(BreakpointSite *bp_site) {
678   if (m_comm.LocalBreakpointsAreSupported()) {
679     Status error;
680     if (bp_site->IsEnabled()) {
681       BreakpointSite::Type bp_type = bp_site->GetType();
682       if (bp_type == BreakpointSite::eExternal) {
683         if (m_destroy_in_process && m_comm.IsRunning()) {
684           // We are trying to destroy our connection and we are running
685           bp_site->SetEnabled(false);
686         } else {
687           if (m_comm.SendRequestBreakpoint(false, bp_site->GetLoadAddress()))
688             bp_site->SetEnabled(false);
689           else
690             error.SetErrorString("KDP remove breakpoint failed");
691         }
692       } else {
693         error = DisableSoftwareBreakpoint(bp_site);
694       }
695     }
696     return error;
697   }
698   return DisableSoftwareBreakpoint(bp_site);
699 }
700 
701 Status ProcessKDP::EnableWatchpoint(Watchpoint *wp, bool notify) {
702   Status error;
703   error.SetErrorString(
704       "watchpoints are not suppported in kdp remote debugging");
705   return error;
706 }
707 
708 Status ProcessKDP::DisableWatchpoint(Watchpoint *wp, bool notify) {
709   Status error;
710   error.SetErrorString(
711       "watchpoints are not suppported in kdp remote debugging");
712   return error;
713 }
714 
715 void ProcessKDP::Clear() { m_thread_list.Clear(); }
716 
717 Status ProcessKDP::DoSignal(int signo) {
718   Status error;
719   error.SetErrorString(
720       "sending signals is not suppported in kdp remote debugging");
721   return error;
722 }
723 
724 void ProcessKDP::Initialize() {
725   static llvm::once_flag g_once_flag;
726 
727   llvm::call_once(g_once_flag, []() {
728     PluginManager::RegisterPlugin(GetPluginNameStatic(),
729                                   GetPluginDescriptionStatic(), CreateInstance,
730                                   DebuggerInitialize);
731 
732     ProcessKDPLog::Initialize();
733   });
734 }
735 
736 void ProcessKDP::DebuggerInitialize(lldb_private::Debugger &debugger) {
737   if (!PluginManager::GetSettingForProcessPlugin(
738           debugger, PluginProperties::GetSettingName())) {
739     const bool is_global_setting = true;
740     PluginManager::CreateSettingForProcessPlugin(
741         debugger, GetGlobalPluginProperties()->GetValueProperties(),
742         ConstString("Properties for the kdp-remote process plug-in."),
743         is_global_setting);
744   }
745 }
746 
747 bool ProcessKDP::StartAsyncThread() {
748   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_PROCESS));
749 
750   if (log)
751     log->Printf("ProcessKDP::StartAsyncThread ()");
752 
753   if (m_async_thread.IsJoinable())
754     return true;
755 
756   m_async_thread = ThreadLauncher::LaunchThread(
757       "<lldb.process.kdp-remote.async>", ProcessKDP::AsyncThread, this, NULL);
758   return m_async_thread.IsJoinable();
759 }
760 
761 void ProcessKDP::StopAsyncThread() {
762   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_PROCESS));
763 
764   if (log)
765     log->Printf("ProcessKDP::StopAsyncThread ()");
766 
767   m_async_broadcaster.BroadcastEvent(eBroadcastBitAsyncThreadShouldExit);
768 
769   // Stop the stdio thread
770   if (m_async_thread.IsJoinable())
771     m_async_thread.Join(nullptr);
772 }
773 
774 void *ProcessKDP::AsyncThread(void *arg) {
775   ProcessKDP *process = (ProcessKDP *)arg;
776 
777   const lldb::pid_t pid = process->GetID();
778 
779   Log *log(ProcessKDPLog::GetLogIfAllCategoriesSet(KDP_LOG_PROCESS));
780   if (log)
781     log->Printf("ProcessKDP::AsyncThread (arg = %p, pid = %" PRIu64
782                 ") thread starting...",
783                 arg, pid);
784 
785   ListenerSP listener_sp(Listener::MakeListener("ProcessKDP::AsyncThread"));
786   EventSP event_sp;
787   const uint32_t desired_event_mask =
788       eBroadcastBitAsyncContinue | eBroadcastBitAsyncThreadShouldExit;
789 
790   if (listener_sp->StartListeningForEvents(&process->m_async_broadcaster,
791                                            desired_event_mask) ==
792       desired_event_mask) {
793     bool done = false;
794     while (!done) {
795       if (log)
796         log->Printf("ProcessKDP::AsyncThread (pid = %" PRIu64
797                     ") listener.WaitForEvent (NULL, event_sp)...",
798                     pid);
799       if (listener_sp->GetEvent(event_sp, llvm::None)) {
800         uint32_t event_type = event_sp->GetType();
801         if (log)
802           log->Printf("ProcessKDP::AsyncThread (pid = %" PRIu64
803                       ") Got an event of type: %d...",
804                       pid, event_type);
805 
806         // When we are running, poll for 1 second to try and get an exception
807         // to indicate the process has stopped. If we don't get one, check to
808         // make sure no one asked us to exit
809         bool is_running = false;
810         DataExtractor exc_reply_packet;
811         do {
812           switch (event_type) {
813           case eBroadcastBitAsyncContinue: {
814             is_running = true;
815             if (process->m_comm.WaitForPacketWithTimeoutMicroSeconds(
816                     exc_reply_packet, 1 * USEC_PER_SEC)) {
817               ThreadSP thread_sp(process->GetKernelThread());
818               if (thread_sp) {
819                 lldb::RegisterContextSP reg_ctx_sp(
820                     thread_sp->GetRegisterContext());
821                 if (reg_ctx_sp)
822                   reg_ctx_sp->InvalidateAllRegisters();
823                 static_cast<ThreadKDP *>(thread_sp.get())
824                     ->SetStopInfoFrom_KDP_EXCEPTION(exc_reply_packet);
825               }
826 
827               // TODO: parse the stop reply packet
828               is_running = false;
829               process->SetPrivateState(eStateStopped);
830             } else {
831               // Check to see if we are supposed to exit. There is no way to
832               // interrupt a running kernel, so all we can do is wait for an
833               // exception or detach...
834               if (listener_sp->GetEvent(event_sp,
835                                         std::chrono::microseconds(0))) {
836                 // We got an event, go through the loop again
837                 event_type = event_sp->GetType();
838               }
839             }
840           } break;
841 
842           case eBroadcastBitAsyncThreadShouldExit:
843             if (log)
844               log->Printf("ProcessKDP::AsyncThread (pid = %" PRIu64
845                           ") got eBroadcastBitAsyncThreadShouldExit...",
846                           pid);
847             done = true;
848             is_running = false;
849             break;
850 
851           default:
852             if (log)
853               log->Printf("ProcessKDP::AsyncThread (pid = %" PRIu64
854                           ") got unknown event 0x%8.8x",
855                           pid, event_type);
856             done = true;
857             is_running = false;
858             break;
859           }
860         } while (is_running);
861       } else {
862         if (log)
863           log->Printf("ProcessKDP::AsyncThread (pid = %" PRIu64
864                       ") listener.WaitForEvent (NULL, event_sp) => false",
865                       pid);
866         done = true;
867       }
868     }
869   }
870 
871   if (log)
872     log->Printf("ProcessKDP::AsyncThread (arg = %p, pid = %" PRIu64
873                 ") thread exiting...",
874                 arg, pid);
875 
876   process->m_async_thread.Reset();
877   return NULL;
878 }
879 
880 class CommandObjectProcessKDPPacketSend : public CommandObjectParsed {
881 private:
882   OptionGroupOptions m_option_group;
883   OptionGroupUInt64 m_command_byte;
884   OptionGroupString m_packet_data;
885 
886   virtual Options *GetOptions() { return &m_option_group; }
887 
888 public:
889   CommandObjectProcessKDPPacketSend(CommandInterpreter &interpreter)
890       : CommandObjectParsed(interpreter, "process plugin packet send",
891                             "Send a custom packet through the KDP protocol by "
892                             "specifying the command byte and the packet "
893                             "payload data. A packet will be sent with a "
894                             "correct header and payload, and the raw result "
895                             "bytes will be displayed as a string value. ",
896                             NULL),
897         m_option_group(),
898         m_command_byte(LLDB_OPT_SET_1, true, "command", 'c', 0, eArgTypeNone,
899                        "Specify the command byte to use when sending the KDP "
900                        "request packet.",
901                        0),
902         m_packet_data(LLDB_OPT_SET_1, false, "payload", 'p', 0, eArgTypeNone,
903                       "Specify packet payload bytes as a hex ASCII string with "
904                       "no spaces or hex prefixes.",
905                       NULL) {
906     m_option_group.Append(&m_command_byte, LLDB_OPT_SET_ALL, LLDB_OPT_SET_1);
907     m_option_group.Append(&m_packet_data, LLDB_OPT_SET_ALL, LLDB_OPT_SET_1);
908     m_option_group.Finalize();
909   }
910 
911   ~CommandObjectProcessKDPPacketSend() {}
912 
913   bool DoExecute(Args &command, CommandReturnObject &result) {
914     const size_t argc = command.GetArgumentCount();
915     if (argc == 0) {
916       if (!m_command_byte.GetOptionValue().OptionWasSet()) {
917         result.AppendError(
918             "the --command option must be set to a valid command byte");
919         result.SetStatus(eReturnStatusFailed);
920       } else {
921         const uint64_t command_byte =
922             m_command_byte.GetOptionValue().GetUInt64Value(0);
923         if (command_byte > 0 && command_byte <= UINT8_MAX) {
924           ProcessKDP *process =
925               (ProcessKDP *)m_interpreter.GetExecutionContext().GetProcessPtr();
926           if (process) {
927             const StateType state = process->GetState();
928 
929             if (StateIsStoppedState(state, true)) {
930               std::vector<uint8_t> payload_bytes;
931               const char *ascii_hex_bytes_cstr =
932                   m_packet_data.GetOptionValue().GetCurrentValue();
933               if (ascii_hex_bytes_cstr && ascii_hex_bytes_cstr[0]) {
934                 StringExtractor extractor(ascii_hex_bytes_cstr);
935                 const size_t ascii_hex_bytes_cstr_len =
936                     extractor.GetStringRef().size();
937                 if (ascii_hex_bytes_cstr_len & 1) {
938                   result.AppendErrorWithFormat("payload data must contain an "
939                                                "even number of ASCII hex "
940                                                "characters: '%s'",
941                                                ascii_hex_bytes_cstr);
942                   result.SetStatus(eReturnStatusFailed);
943                   return false;
944                 }
945                 payload_bytes.resize(ascii_hex_bytes_cstr_len / 2);
946                 if (extractor.GetHexBytes(payload_bytes, '\xdd') !=
947                     payload_bytes.size()) {
948                   result.AppendErrorWithFormat("payload data must only contain "
949                                                "ASCII hex characters (no "
950                                                "spaces or hex prefixes): '%s'",
951                                                ascii_hex_bytes_cstr);
952                   result.SetStatus(eReturnStatusFailed);
953                   return false;
954                 }
955               }
956               Status error;
957               DataExtractor reply;
958               process->GetCommunication().SendRawRequest(
959                   command_byte,
960                   payload_bytes.empty() ? NULL : payload_bytes.data(),
961                   payload_bytes.size(), reply, error);
962 
963               if (error.Success()) {
964                 // Copy the binary bytes into a hex ASCII string for the result
965                 StreamString packet;
966                 packet.PutBytesAsRawHex8(
967                     reply.GetDataStart(), reply.GetByteSize(),
968                     endian::InlHostByteOrder(), endian::InlHostByteOrder());
969                 result.AppendMessage(packet.GetString());
970                 result.SetStatus(eReturnStatusSuccessFinishResult);
971                 return true;
972               } else {
973                 const char *error_cstr = error.AsCString();
974                 if (error_cstr && error_cstr[0])
975                   result.AppendError(error_cstr);
976                 else
977                   result.AppendErrorWithFormat("unknown error 0x%8.8x",
978                                                error.GetError());
979                 result.SetStatus(eReturnStatusFailed);
980                 return false;
981               }
982             } else {
983               result.AppendErrorWithFormat("process must be stopped in order "
984                                            "to send KDP packets, state is %s",
985                                            StateAsCString(state));
986               result.SetStatus(eReturnStatusFailed);
987             }
988           } else {
989             result.AppendError("invalid process");
990             result.SetStatus(eReturnStatusFailed);
991           }
992         } else {
993           result.AppendErrorWithFormat("invalid command byte 0x%" PRIx64
994                                        ", valid values are 1 - 255",
995                                        command_byte);
996           result.SetStatus(eReturnStatusFailed);
997         }
998       }
999     } else {
1000       result.AppendErrorWithFormat("'%s' takes no arguments, only options.",
1001                                    m_cmd_name.c_str());
1002       result.SetStatus(eReturnStatusFailed);
1003     }
1004     return false;
1005   }
1006 };
1007 
1008 class CommandObjectProcessKDPPacket : public CommandObjectMultiword {
1009 private:
1010 public:
1011   CommandObjectProcessKDPPacket(CommandInterpreter &interpreter)
1012       : CommandObjectMultiword(interpreter, "process plugin packet",
1013                                "Commands that deal with KDP remote packets.",
1014                                NULL) {
1015     LoadSubCommand(
1016         "send",
1017         CommandObjectSP(new CommandObjectProcessKDPPacketSend(interpreter)));
1018   }
1019 
1020   ~CommandObjectProcessKDPPacket() {}
1021 };
1022 
1023 class CommandObjectMultiwordProcessKDP : public CommandObjectMultiword {
1024 public:
1025   CommandObjectMultiwordProcessKDP(CommandInterpreter &interpreter)
1026       : CommandObjectMultiword(
1027             interpreter, "process plugin",
1028             "Commands for operating on a ProcessKDP process.",
1029             "process plugin <subcommand> [<subcommand-options>]") {
1030     LoadSubCommand("packet", CommandObjectSP(new CommandObjectProcessKDPPacket(
1031                                  interpreter)));
1032   }
1033 
1034   ~CommandObjectMultiwordProcessKDP() {}
1035 };
1036 
1037 CommandObject *ProcessKDP::GetPluginCommandObject() {
1038   if (!m_command_sp)
1039     m_command_sp.reset(new CommandObjectMultiwordProcessKDP(
1040         GetTarget().GetDebugger().GetCommandInterpreter()));
1041   return m_command_sp.get();
1042 }
1043