xref: /llvm-project/lldb/source/Plugins/ObjectFile/Mach-O/ObjectFileMachO.h (revision 448ac7d3418a31d35b462440c8bf644287efac8a)
1 //===-- ObjectFileMachO.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_OBJECTFILE_MACH_O_OBJECTFILEMACHO_H
10 #define LLDB_SOURCE_PLUGINS_OBJECTFILE_MACH_O_OBJECTFILEMACHO_H
11 
12 #include "lldb/Core/Address.h"
13 #include "lldb/Host/SafeMachO.h"
14 #include "lldb/Symbol/ObjectFile.h"
15 #include "lldb/Symbol/SaveCoreOptions.h"
16 #include "lldb/Utility/FileSpec.h"
17 #include "lldb/Utility/FileSpecList.h"
18 #include "lldb/Utility/RangeMap.h"
19 #include "lldb/Utility/StreamString.h"
20 #include "lldb/Utility/UUID.h"
21 #include <optional>
22 
23 // This class needs to be hidden as eventually belongs in a plugin that
24 // will export the ObjectFile protocol
25 class ObjectFileMachO : public lldb_private::ObjectFile {
26 public:
27   ObjectFileMachO(const lldb::ModuleSP &module_sp, lldb::DataBufferSP data_sp,
28                   lldb::offset_t data_offset,
29                   const lldb_private::FileSpec *file, lldb::offset_t offset,
30                   lldb::offset_t length);
31 
32   ObjectFileMachO(const lldb::ModuleSP &module_sp,
33                   lldb::WritableDataBufferSP data_sp,
34                   const lldb::ProcessSP &process_sp, lldb::addr_t header_addr);
35 
36   ~ObjectFileMachO() override = default;
37 
38   // Static Functions
39   static void Initialize();
40 
41   static void Terminate();
42 
43   static llvm::StringRef GetPluginNameStatic() { return "mach-o"; }
44 
45   static llvm::StringRef GetPluginDescriptionStatic() {
46     return "Mach-o object file reader (32 and 64 bit)";
47   }
48 
49   static lldb_private::ObjectFile *
50   CreateInstance(const lldb::ModuleSP &module_sp, lldb::DataBufferSP data_sp,
51                  lldb::offset_t data_offset, const lldb_private::FileSpec *file,
52                  lldb::offset_t file_offset, lldb::offset_t length);
53 
54   static lldb_private::ObjectFile *CreateMemoryInstance(
55       const lldb::ModuleSP &module_sp, lldb::WritableDataBufferSP data_sp,
56       const lldb::ProcessSP &process_sp, lldb::addr_t header_addr);
57 
58   static size_t GetModuleSpecifications(const lldb_private::FileSpec &file,
59                                         lldb::DataBufferSP &data_sp,
60                                         lldb::offset_t data_offset,
61                                         lldb::offset_t file_offset,
62                                         lldb::offset_t length,
63                                         lldb_private::ModuleSpecList &specs);
64 
65   static bool SaveCore(const lldb::ProcessSP &process_sp,
66                        lldb_private::SaveCoreOptions &options,
67                        lldb_private::Status &error);
68 
69   static bool MagicBytesMatch(lldb::DataBufferSP data_sp, lldb::addr_t offset,
70                               lldb::addr_t length);
71 
72   // LLVM RTTI support
73   static char ID;
74   bool isA(const void *ClassID) const override {
75     return ClassID == &ID || ObjectFile::isA(ClassID);
76   }
77   static bool classof(const ObjectFile *obj) { return obj->isA(&ID); }
78 
79   // Member Functions
80   bool ParseHeader() override;
81 
82   bool SetLoadAddress(lldb_private::Target &target, lldb::addr_t value,
83                       bool value_is_offset) override;
84 
85   lldb::ByteOrder GetByteOrder() const override;
86 
87   bool IsExecutable() const override;
88 
89   bool IsDynamicLoader() const;
90 
91   bool IsSharedCacheBinary() const;
92 
93   bool IsKext() const;
94 
95   uint32_t GetAddressByteSize() const override;
96 
97   lldb_private::AddressClass GetAddressClass(lldb::addr_t file_addr) override;
98 
99   void ParseSymtab(lldb_private::Symtab &symtab) override;
100 
101   bool IsStripped() override;
102 
103   void CreateSections(lldb_private::SectionList &unified_section_list) override;
104 
105   void Dump(lldb_private::Stream *s) override;
106 
107   lldb_private::ArchSpec GetArchitecture() override;
108 
109   lldb_private::UUID GetUUID() override;
110 
111   uint32_t GetDependentModules(lldb_private::FileSpecList &files) override;
112 
113   lldb_private::FileSpecList GetReExportedLibraries() override {
114     return m_reexported_dylibs;
115   }
116 
117   lldb_private::Address GetEntryPointAddress() override;
118 
119   lldb_private::Address GetBaseAddress() override;
120 
121   uint32_t GetNumThreadContexts() override;
122 
123   std::vector<std::tuple<lldb::offset_t, lldb::offset_t>>
124   FindLC_NOTEByName(std::string name);
125 
126   std::string GetIdentifierString() override;
127 
128   lldb_private::AddressableBits GetAddressableBits() override;
129 
130   bool GetCorefileMainBinaryInfo(lldb::addr_t &value, bool &value_is_offset,
131                                  lldb_private::UUID &uuid,
132                                  ObjectFile::BinaryType &type) override;
133 
134   bool GetCorefileThreadExtraInfos(std::vector<lldb::tid_t> &tids) override;
135 
136   bool LoadCoreFileImages(lldb_private::Process &process) override;
137 
138   lldb::RegisterContextSP
139   GetThreadContextAtIndex(uint32_t idx, lldb_private::Thread &thread) override;
140 
141   ObjectFile::Type CalculateType() override;
142 
143   ObjectFile::Strata CalculateStrata() override;
144 
145   llvm::VersionTuple GetVersion() override;
146 
147   llvm::VersionTuple GetMinimumOSVersion() override;
148 
149   llvm::VersionTuple GetSDKVersion() override;
150 
151   bool GetIsDynamicLinkEditor() override;
152 
153   bool CanTrustAddressRanges() override;
154 
155   static bool ParseHeader(lldb_private::DataExtractor &data,
156                           lldb::offset_t *data_offset_ptr,
157                           llvm::MachO::mach_header &header);
158 
159   bool AllowAssemblyEmulationUnwindPlans() override;
160 
161   lldb_private::Section *GetMachHeaderSection();
162 
163   // PluginInterface protocol
164   llvm::StringRef GetPluginName() override { return GetPluginNameStatic(); }
165 
166 protected:
167   static lldb_private::UUID
168   GetUUID(const llvm::MachO::mach_header &header,
169           const lldb_private::DataExtractor &data,
170           lldb::offset_t lc_offset); // Offset to the first load command
171 
172   static lldb_private::ArchSpec GetArchitecture(
173       lldb::ModuleSP module_sp, const llvm::MachO::mach_header &header,
174       const lldb_private::DataExtractor &data, lldb::offset_t lc_offset);
175 
176   /// Enumerate all ArchSpecs supported by this Mach-O file.
177   ///
178   /// On macOS one Mach-O slice can contain multiple load commands:
179   /// One load command for being loaded into a macOS process and one
180   /// load command for being loaded into a macCatalyst process. In
181   /// contrast to ObjectContainerUniversalMachO, this is the same
182   /// binary that can be loaded into different contexts.
183   static void GetAllArchSpecs(const llvm::MachO::mach_header &header,
184                               const lldb_private::DataExtractor &data,
185                               lldb::offset_t lc_offset,
186                               lldb_private::ModuleSpec &base_spec,
187                               lldb_private::ModuleSpecList &all_specs);
188 
189   /// Intended for same-host arm device debugging where lldb needs to
190   /// detect libraries in the shared cache and augment the nlist entries
191   /// with an on-disk dyld_shared_cache file.  The process will record
192   /// the shared cache UUID so the on-disk cache can be matched or rejected
193   /// correctly.
194   void GetProcessSharedCacheUUID(lldb_private::Process *,
195                                  lldb::addr_t &base_addr,
196                                  lldb_private::UUID &uuid);
197 
198   /// Intended for same-host arm device debugging where lldb will read
199   /// shared cache libraries out of its own memory instead of the remote
200   /// process' memory as an optimization.  If lldb's shared cache UUID
201   /// does not match the process' shared cache UUID, this optimization
202   /// should not be used.
203   void GetLLDBSharedCacheUUID(lldb::addr_t &base_addir, lldb_private::UUID &uuid);
204 
205   lldb::addr_t CalculateSectionLoadAddressForMemoryImage(
206       lldb::addr_t mach_header_load_address,
207       const lldb_private::Section *mach_header_section,
208       const lldb_private::Section *section);
209 
210   lldb_private::UUID
211   GetSharedCacheUUID(lldb_private::FileSpec dyld_shared_cache,
212                      const lldb::ByteOrder byte_order,
213                      const uint32_t addr_byte_size);
214 
215   size_t ParseSymtab();
216 
217   typedef lldb_private::RangeVector<uint32_t, uint32_t, 8> EncryptedFileRanges;
218   EncryptedFileRanges GetEncryptedFileRanges();
219 
220   struct SegmentParsingContext;
221   void ProcessDysymtabCommand(const llvm::MachO::load_command &load_cmd,
222                               lldb::offset_t offset);
223   void ProcessSegmentCommand(const llvm::MachO::load_command &load_cmd,
224                              lldb::offset_t offset, uint32_t cmd_idx,
225                              SegmentParsingContext &context);
226   void SanitizeSegmentCommand(llvm::MachO::segment_command_64 &seg_cmd,
227                               uint32_t cmd_idx);
228 
229   bool SectionIsLoadable(const lldb_private::Section *section);
230 
231   /// A corefile may include metadata about all of the binaries that were
232   /// present in the process when the corefile was taken.  This is only
233   /// implemented for Mach-O files for now; we'll generalize it when we
234   /// have other systems that can include the same.
235   struct MachOCorefileImageEntry {
236     std::string filename;
237     lldb_private::UUID uuid;
238     lldb::addr_t load_address = LLDB_INVALID_ADDRESS;
239     lldb::addr_t slide = 0;
240     bool currently_executing = false;
241     std::vector<std::tuple<lldb_private::ConstString, lldb::addr_t>>
242         segment_load_addresses;
243   };
244 
245   struct LCNoteEntry {
246     LCNoteEntry(uint32_t addr_byte_size, lldb::ByteOrder byte_order)
247         : payload(lldb_private::Stream::eBinary, addr_byte_size, byte_order) {}
248 
249     std::string name;
250     lldb::addr_t payload_file_offset = 0;
251     lldb_private::StreamString payload;
252   };
253 
254   struct MachOCorefileAllImageInfos {
255     std::vector<MachOCorefileImageEntry> all_image_infos;
256     bool IsValid() { return all_image_infos.size() > 0; }
257   };
258 
259   // The LC_SYMTAB's symtab_command structure uses 32-bit file offsets
260   // for two fields, but ObjectFileMachO needs to calculate the offsets
261   // in virtual address layout from the start of the TEXT segment, and
262   // that span may be larger than 4GB.
263   struct SymtabCommandLargeOffsets {
264     uint32_t cmd = 0;          /* LC_SYMTAB */
265     uint32_t cmdsize = 0;      /* sizeof(struct symtab_command) */
266     lldb::offset_t symoff = 0; /* symbol table offset */
267     uint32_t nsyms = 0;        /* number of symbol table entries */
268     lldb::offset_t stroff = 0; /* string table offset */
269     uint32_t strsize = 0;      /* string table size in bytes */
270   };
271 
272   /// Get the list of binary images that were present in the process
273   /// when the corefile was produced.
274   /// \return
275   ///     The MachOCorefileAllImageInfos object returned will have
276   ///     IsValid() == false if the information is unavailable.
277   MachOCorefileAllImageInfos GetCorefileAllImageInfos();
278 
279   llvm::MachO::mach_header m_header;
280   static lldb_private::ConstString GetSegmentNameTEXT();
281   static lldb_private::ConstString GetSegmentNameDATA();
282   static lldb_private::ConstString GetSegmentNameDATA_DIRTY();
283   static lldb_private::ConstString GetSegmentNameDATA_CONST();
284   static lldb_private::ConstString GetSegmentNameOBJC();
285   static lldb_private::ConstString GetSegmentNameLINKEDIT();
286   static lldb_private::ConstString GetSegmentNameDWARF();
287   static lldb_private::ConstString GetSegmentNameLLVM_COV();
288   static lldb_private::ConstString GetSectionNameEHFrame();
289 
290   llvm::MachO::dysymtab_command m_dysymtab;
291   std::vector<llvm::MachO::section_64> m_mach_sections;
292   std::optional<llvm::VersionTuple> m_min_os_version;
293   std::optional<llvm::VersionTuple> m_sdk_versions;
294   typedef lldb_private::RangeVector<uint32_t, uint32_t> FileRangeArray;
295   lldb_private::Address m_entry_point_address;
296   FileRangeArray m_thread_context_offsets;
297   lldb::offset_t m_linkedit_original_offset = 0;
298   lldb::addr_t m_text_address = LLDB_INVALID_ADDRESS;
299   bool m_thread_context_offsets_valid;
300   lldb_private::FileSpecList m_reexported_dylibs;
301   bool m_allow_assembly_emulation_unwind_plans;
302 };
303 
304 #endif // LLDB_SOURCE_PLUGINS_OBJECTFILE_MACH_O_OBJECTFILEMACHO_H
305