1 //===-- DynamicLoaderMacOSXDYLD.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 // This is the DynamicLoader plugin for Darwin (macOS / iPhoneOS / tvOS / 10 // watchOS / BridgeOS) 11 // platforms earlier than 2016, where lldb would read the "dyld_all_image_infos" 12 // dyld internal structure to understand where things were loaded and the 13 // solib loaded/unloaded notification function we put a breakpoint on gives us 14 // an array of (load address, mod time, file path) tuples. 15 // 16 // As of late 2016, the new DynamicLoaderMacOS plugin should be used, which uses 17 // dyld SPI functions to get the same information without reading internal dyld 18 // data structures. 19 20 #ifndef LLDB_SOURCE_PLUGINS_DYNAMICLOADER_MACOSX_DYLD_DYNAMICLOADERMACOSXDYLD_H 21 #define LLDB_SOURCE_PLUGINS_DYNAMICLOADER_MACOSX_DYLD_DYNAMICLOADERMACOSXDYLD_H 22 23 #include <mutex> 24 #include <vector> 25 26 #include "lldb/Host/SafeMachO.h" 27 #include "lldb/Target/DynamicLoader.h" 28 #include "lldb/Target/Process.h" 29 #include "lldb/Utility/FileSpec.h" 30 #include "lldb/Utility/StructuredData.h" 31 #include "lldb/Utility/UUID.h" 32 33 #include "DynamicLoaderDarwin.h" 34 35 class DynamicLoaderMacOSXDYLD : public lldb_private::DynamicLoaderDarwin { 36 public: 37 DynamicLoaderMacOSXDYLD(lldb_private::Process *process); 38 39 ~DynamicLoaderMacOSXDYLD() override; 40 41 // Static Functions 42 static void Initialize(); 43 44 static void Terminate(); 45 46 static llvm::StringRef GetPluginNameStatic() { return "macosx-dyld"; } 47 48 static llvm::StringRef GetPluginDescriptionStatic(); 49 50 static lldb_private::DynamicLoader * 51 CreateInstance(lldb_private::Process *process, bool force); 52 53 static void DebuggerInitialize(lldb_private::Debugger &debugger); 54 55 /// Called after attaching a process. 56 /// 57 /// Allow DynamicLoader plug-ins to execute some code after 58 /// attaching to a process. 59 bool ProcessDidExec() override; 60 61 lldb_private::Status CanLoadImage() override; 62 63 bool GetSharedCacheInformation( 64 lldb::addr_t &base_address, lldb_private::UUID &uuid, 65 lldb_private::LazyBool &using_shared_cache, 66 lldb_private::LazyBool &private_shared_cache) override; 67 68 // PluginInterface protocol 69 llvm::StringRef GetPluginName() override { return GetPluginNameStatic(); } 70 71 bool IsFullyInitialized() override; 72 73 protected: 74 void PutToLog(lldb_private::Log *log) const; 75 76 void DoInitialImageFetch() override; 77 78 bool NeedToDoInitialImageFetch() override; 79 80 bool DidSetNotificationBreakpoint() override; 81 82 void DoClear() override; 83 84 bool ReadDYLDInfoFromMemoryAndSetNotificationCallback(lldb::addr_t addr); 85 86 static bool 87 NotifyBreakpointHit(void *baton, 88 lldb_private::StoppointCallbackContext *context, 89 lldb::user_id_t break_id, lldb::user_id_t break_loc_id); 90 91 uint32_t AddrByteSize(); 92 93 bool ReadMachHeader(lldb::addr_t addr, llvm::MachO::mach_header *header, 94 lldb_private::DataExtractor *load_command_data); 95 96 uint32_t ParseLoadCommands(const lldb_private::DataExtractor &data, 97 ImageInfo &dylib_info, 98 lldb_private::FileSpec *lc_id_dylinker); 99 100 struct DYLDAllImageInfos { 101 uint32_t version = 0; 102 uint32_t dylib_info_count = 0; // Version >= 1 103 lldb::addr_t dylib_info_addr = LLDB_INVALID_ADDRESS; // Version >= 1 104 lldb::addr_t notification = LLDB_INVALID_ADDRESS; // Version >= 1 105 bool processDetachedFromSharedRegion = false; // Version >= 1 106 bool libSystemInitialized = false; // Version >= 2 107 lldb::addr_t dyldImageLoadAddress = LLDB_INVALID_ADDRESS; // Version >= 2 108 109 DYLDAllImageInfos() = default; 110 111 void Clear() { 112 version = 0; 113 dylib_info_count = 0; 114 dylib_info_addr = LLDB_INVALID_ADDRESS; 115 notification = LLDB_INVALID_ADDRESS; 116 processDetachedFromSharedRegion = false; 117 libSystemInitialized = false; 118 dyldImageLoadAddress = LLDB_INVALID_ADDRESS; 119 } 120 121 bool IsValid() const { return version >= 1 && version <= 6; } 122 }; 123 124 static lldb::ByteOrder GetByteOrderFromMagic(uint32_t magic); 125 126 bool SetNotificationBreakpoint() override; 127 128 void ClearNotificationBreakpoint() override; 129 130 // There is a little tricky bit where you might initially attach while dyld is 131 // updating 132 // the all_image_infos, and you can't read the infos, so you have to continue 133 // and pick it 134 // up when you hit the update breakpoint. At that point, you need to run this 135 // initialize 136 // function, but when you do it that way you DON'T need to do the extra work 137 // you would at 138 // the breakpoint. 139 // So this function will only do actual work if the image infos haven't been 140 // read yet. 141 // If it does do any work, then it will return true, and false otherwise. 142 // That way you can 143 // call it in the breakpoint action, and if it returns true you're done. 144 bool InitializeFromAllImageInfos(); 145 146 bool ReadAllImageInfosStructure(); 147 148 bool AddModulesUsingImageInfosAddress(lldb::addr_t image_infos_addr, 149 uint32_t image_infos_count); 150 151 bool RemoveModulesUsingImageInfosAddress(lldb::addr_t image_infos_addr, 152 uint32_t image_infos_count); 153 154 void UpdateImageInfosHeaderAndLoadCommands(ImageInfo::collection &image_infos, 155 uint32_t infos_count, 156 bool update_executable); 157 158 bool ReadImageInfos(lldb::addr_t image_infos_addr, uint32_t image_infos_count, 159 ImageInfo::collection &image_infos); 160 161 lldb::addr_t m_dyld_all_image_infos_addr; 162 DYLDAllImageInfos m_dyld_all_image_infos; 163 uint32_t m_dyld_all_image_infos_stop_id; 164 lldb::user_id_t m_break_id; 165 mutable std::recursive_mutex m_mutex; 166 bool m_process_image_addr_is_all_images_infos; 167 168 private: 169 DynamicLoaderMacOSXDYLD(const DynamicLoaderMacOSXDYLD &) = delete; 170 const DynamicLoaderMacOSXDYLD & 171 operator=(const DynamicLoaderMacOSXDYLD &) = delete; 172 }; 173 174 #endif // LLDB_SOURCE_PLUGINS_DYNAMICLOADER_MACOSX_DYLD_DYNAMICLOADERMACOSXDYLD_H 175