1 //===-- ProcessGDBRemote.h --------------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef LLDB_SOURCE_PLUGINS_PROCESS_GDB_REMOTE_PROCESSGDBREMOTE_H
10 #define LLDB_SOURCE_PLUGINS_PROCESS_GDB_REMOTE_PROCESSGDBREMOTE_H
11 
12 #include <atomic>
13 #include <map>
14 #include <mutex>
15 #include <string>
16 #include <vector>
17 
18 #include "lldb/Core/LoadedModuleInfoList.h"
19 #include "lldb/Core/ModuleSpec.h"
20 #include "lldb/Core/ThreadSafeValue.h"
21 #include "lldb/Host/HostThread.h"
22 #include "lldb/Target/Process.h"
23 #include "lldb/Target/Thread.h"
24 #include "lldb/Utility/ArchSpec.h"
25 #include "lldb/Utility/Broadcaster.h"
26 #include "lldb/Utility/ConstString.h"
27 #include "lldb/Utility/GDBRemote.h"
28 #include "lldb/Utility/Status.h"
29 #include "lldb/Utility/StreamString.h"
30 #include "lldb/Utility/StringExtractor.h"
31 #include "lldb/Utility/StringList.h"
32 #include "lldb/Utility/StructuredData.h"
33 #include "lldb/lldb-private-forward.h"
34 
35 #include "GDBRemoteCommunicationClient.h"
36 #include "GDBRemoteCommunicationReplayServer.h"
37 #include "GDBRemoteRegisterContext.h"
38 
39 #include "llvm/ADT/DenseMap.h"
40 
41 namespace lldb_private {
42 namespace repro {
43 class Loader;
44 }
45 namespace process_gdb_remote {
46 
47 struct RemoteRegisterInfo {
48   ConstString name;
49   ConstString alt_name;
50   ConstString set_name;
51   uint32_t byte_size = LLDB_INVALID_INDEX32;
52   uint32_t byte_offset = LLDB_INVALID_INDEX32;
53   lldb::Encoding encoding = lldb::eEncodingUint;
54   lldb::Format format = lldb::eFormatHex;
55   uint32_t regnum_dwarf = LLDB_INVALID_REGNUM;
56   uint32_t regnum_ehframe = LLDB_INVALID_REGNUM;
57   uint32_t regnum_generic = LLDB_INVALID_REGNUM;
58   uint32_t regnum_remote = LLDB_INVALID_REGNUM;
59   std::vector<uint32_t> value_regs;
60   std::vector<uint32_t> invalidate_regs;
61 };
62 
63 class ThreadGDBRemote;
64 
65 class ProcessGDBRemote : public Process,
66                          private GDBRemoteClientBase::ContinueDelegate {
67 public:
68   ProcessGDBRemote(lldb::TargetSP target_sp, lldb::ListenerSP listener_sp);
69 
70   ~ProcessGDBRemote() override;
71 
72   static lldb::ProcessSP CreateInstance(lldb::TargetSP target_sp,
73                                         lldb::ListenerSP listener_sp,
74                                         const FileSpec *crash_file_path,
75                                         bool can_connect);
76 
77   static void Initialize();
78 
79   static void DebuggerInitialize(Debugger &debugger);
80 
81   static void Terminate();
82 
83   static ConstString GetPluginNameStatic();
84 
85   static const char *GetPluginDescriptionStatic();
86 
87   static std::chrono::seconds GetPacketTimeout();
88 
89   // Check if a given Process
90   bool CanDebug(lldb::TargetSP target_sp,
91                 bool plugin_specified_by_name) override;
92 
93   CommandObject *GetPluginCommandObject() override;
94 
95   // Creating a new process, or attaching to an existing one
96   Status WillLaunch(Module *module) override;
97 
98   Status DoLaunch(Module *exe_module, ProcessLaunchInfo &launch_info) override;
99 
100   void DidLaunch() override;
101 
102   Status WillAttachToProcessWithID(lldb::pid_t pid) override;
103 
104   Status WillAttachToProcessWithName(const char *process_name,
105                                      bool wait_for_launch) override;
106 
107   Status DoConnectRemote(llvm::StringRef remote_url) override;
108 
109   Status WillLaunchOrAttach();
110 
111   Status DoAttachToProcessWithID(lldb::pid_t pid,
112                                  const ProcessAttachInfo &attach_info) override;
113 
114   Status
115   DoAttachToProcessWithName(const char *process_name,
116                             const ProcessAttachInfo &attach_info) override;
117 
118   void DidAttach(ArchSpec &process_arch) override;
119 
120   // PluginInterface protocol
121   ConstString GetPluginName() override;
122 
123   // Process Control
124   Status WillResume() override;
125 
126   Status DoResume() override;
127 
128   Status DoHalt(bool &caused_stop) override;
129 
130   Status DoDetach(bool keep_stopped) override;
131 
132   bool DetachRequiresHalt() override { return true; }
133 
134   Status DoSignal(int signal) override;
135 
136   Status DoDestroy() override;
137 
138   void RefreshStateAfterStop() override;
139 
140   void SetUnixSignals(const lldb::UnixSignalsSP &signals_sp);
141 
142   // Process Queries
143   bool IsAlive() override;
144 
145   lldb::addr_t GetImageInfoAddress() override;
146 
147   void WillPublicStop() override;
148 
149   // Process Memory
150   size_t DoReadMemory(lldb::addr_t addr, void *buf, size_t size,
151                       Status &error) override;
152 
153   Status
154   WriteObjectFile(std::vector<ObjectFile::LoadableData> entries) override;
155 
156   size_t DoWriteMemory(lldb::addr_t addr, const void *buf, size_t size,
157                        Status &error) override;
158 
159   lldb::addr_t DoAllocateMemory(size_t size, uint32_t permissions,
160                                 Status &error) override;
161 
162   Status GetMemoryRegionInfo(lldb::addr_t load_addr,
163                              MemoryRegionInfo &region_info) override;
164 
165   Status DoDeallocateMemory(lldb::addr_t ptr) override;
166 
167   // Process STDIO
168   size_t PutSTDIN(const char *buf, size_t buf_size, Status &error) override;
169 
170   // Process Breakpoints
171   Status EnableBreakpointSite(BreakpointSite *bp_site) override;
172 
173   Status DisableBreakpointSite(BreakpointSite *bp_site) override;
174 
175   // Process Watchpoints
176   Status EnableWatchpoint(Watchpoint *wp, bool notify = true) override;
177 
178   Status DisableWatchpoint(Watchpoint *wp, bool notify = true) override;
179 
180   Status GetWatchpointSupportInfo(uint32_t &num) override;
181 
182   llvm::Expected<TraceSupportedResponse> TraceSupported() override;
183 
184   llvm::Error TraceStop(const TraceStopRequest &request) override;
185 
186   llvm::Error TraceStart(const llvm::json::Value &request) override;
187 
188   llvm::Expected<std::string> TraceGetState(llvm::StringRef type) override;
189 
190   llvm::Expected<std::vector<uint8_t>>
191   TraceGetBinaryData(const TraceGetBinaryDataRequest &request) override;
192 
193   Status GetWatchpointSupportInfo(uint32_t &num, bool &after) override;
194 
195   bool StartNoticingNewThreads() override;
196 
197   bool StopNoticingNewThreads() override;
198 
199   GDBRemoteCommunicationClient &GetGDBRemote() { return m_gdb_comm; }
200 
201   Status SendEventData(const char *data) override;
202 
203   // Override DidExit so we can disconnect from the remote GDB server
204   void DidExit() override;
205 
206   void SetUserSpecifiedMaxMemoryTransferSize(uint64_t user_specified_max);
207 
208   bool GetModuleSpec(const FileSpec &module_file_spec, const ArchSpec &arch,
209                      ModuleSpec &module_spec) override;
210 
211   void PrefetchModuleSpecs(llvm::ArrayRef<FileSpec> module_file_specs,
212                            const llvm::Triple &triple) override;
213 
214   llvm::VersionTuple GetHostOSVersion() override;
215   llvm::VersionTuple GetHostMacCatalystVersion() override;
216 
217   llvm::Error LoadModules() override;
218 
219   llvm::Expected<LoadedModuleInfoList> GetLoadedModuleList() override;
220 
221   Status GetFileLoadAddress(const FileSpec &file, bool &is_loaded,
222                             lldb::addr_t &load_addr) override;
223 
224   void ModulesDidLoad(ModuleList &module_list) override;
225 
226   StructuredData::ObjectSP
227   GetLoadedDynamicLibrariesInfos(lldb::addr_t image_list_address,
228                                  lldb::addr_t image_count) override;
229 
230   Status
231   ConfigureStructuredData(ConstString type_name,
232                           const StructuredData::ObjectSP &config_sp) override;
233 
234   StructuredData::ObjectSP GetLoadedDynamicLibrariesInfos() override;
235 
236   StructuredData::ObjectSP GetLoadedDynamicLibrariesInfos(
237       const std::vector<lldb::addr_t> &load_addresses) override;
238 
239   StructuredData::ObjectSP
240   GetLoadedDynamicLibrariesInfos_sender(StructuredData::ObjectSP args);
241 
242   StructuredData::ObjectSP GetSharedCacheInfo() override;
243 
244   std::string HarmonizeThreadIdsForProfileData(
245       StringExtractorGDBRemote &inputStringExtractor);
246 
247   void DidFork(lldb::pid_t child_pid, lldb::tid_t child_tid) override;
248   void DidVFork(lldb::pid_t child_pid, lldb::tid_t child_tid) override;
249   void DidVForkDone() override;
250   void DidExec() override;
251 
252   llvm::Expected<bool> SaveCore(llvm::StringRef outfile) override;
253 
254 protected:
255   friend class ThreadGDBRemote;
256   friend class GDBRemoteCommunicationClient;
257   friend class GDBRemoteRegisterContext;
258 
259   bool SupportsMemoryTagging() override;
260 
261   /// Broadcaster event bits definitions.
262   enum {
263     eBroadcastBitAsyncContinue = (1 << 0),
264     eBroadcastBitAsyncThreadShouldExit = (1 << 1),
265     eBroadcastBitAsyncThreadDidExit = (1 << 2)
266   };
267 
268   GDBRemoteCommunicationClient m_gdb_comm;
269   GDBRemoteCommunicationReplayServer m_gdb_replay_server;
270   std::atomic<lldb::pid_t> m_debugserver_pid;
271 
272   llvm::Optional<StringExtractorGDBRemote> m_last_stop_packet;
273   std::recursive_mutex m_last_stop_packet_mutex;
274 
275   GDBRemoteDynamicRegisterInfoSP m_register_info_sp;
276   Broadcaster m_async_broadcaster;
277   lldb::ListenerSP m_async_listener_sp;
278   HostThread m_async_thread;
279   std::recursive_mutex m_async_thread_state_mutex;
280   typedef std::vector<lldb::tid_t> tid_collection;
281   typedef std::vector<std::pair<lldb::tid_t, int>> tid_sig_collection;
282   typedef std::map<lldb::addr_t, lldb::addr_t> MMapMap;
283   typedef std::map<uint32_t, std::string> ExpeditedRegisterMap;
284   tid_collection m_thread_ids; // Thread IDs for all threads. This list gets
285                                // updated after stopping
286   std::vector<lldb::addr_t> m_thread_pcs;     // PC values for all the threads.
287   StructuredData::ObjectSP m_jstopinfo_sp;    // Stop info only for any threads
288                                               // that have valid stop infos
289   StructuredData::ObjectSP m_jthreadsinfo_sp; // Full stop info, expedited
290                                               // registers and memory for all
291                                               // threads if "jThreadsInfo"
292                                               // packet is supported
293   tid_collection m_continue_c_tids;           // 'c' for continue
294   tid_sig_collection m_continue_C_tids;       // 'C' for continue with signal
295   tid_collection m_continue_s_tids;           // 's' for step
296   tid_sig_collection m_continue_S_tids;       // 'S' for step with signal
297   uint64_t m_max_memory_size; // The maximum number of bytes to read/write when
298                               // reading and writing memory
299   uint64_t m_remote_stub_max_memory_size; // The maximum memory size the remote
300                                           // gdb stub can handle
301   MMapMap m_addr_to_mmap_size;
302   lldb::BreakpointSP m_thread_create_bp_sp;
303   bool m_waiting_for_attach;
304   bool m_destroy_tried_resuming;
305   lldb::CommandObjectSP m_command_sp;
306   int64_t m_breakpoint_pc_offset;
307   lldb::tid_t m_initial_tid; // The initial thread ID, given by stub on attach
308   bool m_use_g_packet_for_reading;
309 
310   bool m_replay_mode;
311   bool m_allow_flash_writes;
312   using FlashRangeVector = lldb_private::RangeVector<lldb::addr_t, size_t>;
313   using FlashRange = FlashRangeVector::Entry;
314   FlashRangeVector m_erased_flash_ranges;
315 
316   bool m_vfork_in_progress;
317 
318   // Accessors
319   bool IsRunning(lldb::StateType state) {
320     return state == lldb::eStateRunning || IsStepping(state);
321   }
322 
323   bool IsStepping(lldb::StateType state) {
324     return state == lldb::eStateStepping;
325   }
326 
327   bool CanResume(lldb::StateType state) { return state == lldb::eStateStopped; }
328 
329   bool HasExited(lldb::StateType state) { return state == lldb::eStateExited; }
330 
331   bool ProcessIDIsValid() const;
332 
333   void Clear();
334 
335   bool DoUpdateThreadList(ThreadList &old_thread_list,
336                           ThreadList &new_thread_list) override;
337 
338   Status ConnectToReplayServer();
339 
340   Status EstablishConnectionIfNeeded(const ProcessInfo &process_info);
341 
342   Status LaunchAndConnectToDebugserver(const ProcessInfo &process_info);
343 
344   void KillDebugserverProcess();
345 
346   void BuildDynamicRegisterInfo(bool force);
347 
348   void SetLastStopPacket(const StringExtractorGDBRemote &response);
349 
350   bool ParsePythonTargetDefinition(const FileSpec &target_definition_fspec);
351 
352   DataExtractor GetAuxvData() override;
353 
354   StructuredData::ObjectSP GetExtendedInfoForThread(lldb::tid_t tid);
355 
356   void GetMaxMemorySize();
357 
358   bool CalculateThreadStopInfo(ThreadGDBRemote *thread);
359 
360   size_t UpdateThreadPCsFromStopReplyThreadsValue(llvm::StringRef value);
361 
362   size_t UpdateThreadIDsFromStopReplyThreadsValue(llvm::StringRef value);
363 
364   bool HandleNotifyPacket(StringExtractorGDBRemote &packet);
365 
366   bool StartAsyncThread();
367 
368   void StopAsyncThread();
369 
370   static lldb::thread_result_t AsyncThread(void *arg);
371 
372   static bool
373   MonitorDebugserverProcess(std::weak_ptr<ProcessGDBRemote> process_wp,
374                             lldb::pid_t pid, bool exited, int signo,
375                             int exit_status);
376 
377   lldb::StateType SetThreadStopInfo(StringExtractor &stop_packet);
378 
379   bool
380   GetThreadStopInfoFromJSON(ThreadGDBRemote *thread,
381                             const StructuredData::ObjectSP &thread_infos_sp);
382 
383   lldb::ThreadSP SetThreadStopInfo(StructuredData::Dictionary *thread_dict);
384 
385   lldb::ThreadSP
386   SetThreadStopInfo(lldb::tid_t tid,
387                     ExpeditedRegisterMap &expedited_register_map, uint8_t signo,
388                     const std::string &thread_name, const std::string &reason,
389                     const std::string &description, uint32_t exc_type,
390                     const std::vector<lldb::addr_t> &exc_data,
391                     lldb::addr_t thread_dispatch_qaddr, bool queue_vars_valid,
392                     lldb_private::LazyBool associated_with_libdispatch_queue,
393                     lldb::addr_t dispatch_queue_t, std::string &queue_name,
394                     lldb::QueueKind queue_kind, uint64_t queue_serial);
395 
396   void HandleStopReplySequence();
397 
398   void ClearThreadIDList();
399 
400   bool UpdateThreadIDList();
401 
402   void DidLaunchOrAttach(ArchSpec &process_arch);
403   void MaybeLoadExecutableModule();
404 
405   Status ConnectToDebugserver(llvm::StringRef host_port);
406 
407   const char *GetDispatchQueueNameForThread(lldb::addr_t thread_dispatch_qaddr,
408                                             std::string &dispatch_queue_name);
409 
410   DynamicLoader *GetDynamicLoader() override;
411 
412   bool GetGDBServerRegisterInfoXMLAndProcess(
413     ArchSpec &arch_to_use, std::string xml_filename,
414     std::vector<RemoteRegisterInfo> &registers);
415 
416   // Convert RemoteRegisterInfos into RegisterInfos and add to the dynamic
417   // register list.
418   void AddRemoteRegisters(std::vector<RemoteRegisterInfo> &registers,
419                           const ArchSpec &arch_to_use);
420   // Query remote GDBServer for register information
421   bool GetGDBServerRegisterInfo(ArchSpec &arch);
422 
423   lldb::ModuleSP LoadModuleAtAddress(const FileSpec &file,
424                                      lldb::addr_t link_map,
425                                      lldb::addr_t base_addr,
426                                      bool value_is_offset);
427 
428   Status UpdateAutomaticSignalFiltering() override;
429 
430   Status FlashErase(lldb::addr_t addr, size_t size);
431 
432   Status FlashDone();
433 
434   bool HasErased(FlashRange range);
435 
436   llvm::Expected<std::vector<uint8_t>>
437   DoReadMemoryTags(lldb::addr_t addr, size_t len, int32_t type) override;
438 
439   Status DoWriteMemoryTags(lldb::addr_t addr, size_t len, int32_t type,
440                            const std::vector<uint8_t> &tags) override;
441 
442 private:
443   // For ProcessGDBRemote only
444   std::string m_partial_profile_data;
445   std::map<uint64_t, uint32_t> m_thread_id_to_used_usec_map;
446   uint64_t m_last_signals_version = 0;
447 
448   static bool NewThreadNotifyBreakpointHit(void *baton,
449                                            StoppointCallbackContext *context,
450                                            lldb::user_id_t break_id,
451                                            lldb::user_id_t break_loc_id);
452 
453   // ContinueDelegate interface
454   void HandleAsyncStdout(llvm::StringRef out) override;
455   void HandleAsyncMisc(llvm::StringRef data) override;
456   void HandleStopReply() override;
457   void HandleAsyncStructuredDataPacket(llvm::StringRef data) override;
458 
459   void SetThreadPc(const lldb::ThreadSP &thread_sp, uint64_t index);
460   using ModuleCacheKey = std::pair<std::string, std::string>;
461   // KeyInfo for the cached module spec DenseMap.
462   // The invariant is that all real keys will have the file and architecture
463   // set.
464   // The empty key has an empty file and an empty arch.
465   // The tombstone key has an invalid arch and an empty file.
466   // The comparison and hash functions take the file name and architecture
467   // triple into account.
468   struct ModuleCacheInfo {
469     static ModuleCacheKey getEmptyKey() { return ModuleCacheKey(); }
470 
471     static ModuleCacheKey getTombstoneKey() { return ModuleCacheKey("", "T"); }
472 
473     static unsigned getHashValue(const ModuleCacheKey &key) {
474       return llvm::hash_combine(key.first, key.second);
475     }
476 
477     static bool isEqual(const ModuleCacheKey &LHS, const ModuleCacheKey &RHS) {
478       return LHS == RHS;
479     }
480   };
481 
482   llvm::DenseMap<ModuleCacheKey, ModuleSpec, ModuleCacheInfo>
483       m_cached_module_specs;
484 
485   ProcessGDBRemote(const ProcessGDBRemote &) = delete;
486   const ProcessGDBRemote &operator=(const ProcessGDBRemote &) = delete;
487 
488   // fork helpers
489   void DidForkSwitchSoftwareBreakpoints(bool enable);
490   void DidForkSwitchHardwareTraps(bool enable);
491 };
492 
493 } // namespace process_gdb_remote
494 } // namespace lldb_private
495 
496 #endif // LLDB_SOURCE_PLUGINS_PROCESS_GDB_REMOTE_PROCESSGDBREMOTE_H
497