1 //===-- DynamicLoaderDarwinKernel.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 #include "lldb/lldb-python.h"
11 
12 #include "lldb/Utility/SafeMachO.h"
13 
14 #include "lldb/Breakpoint/StoppointCallbackContext.h"
15 #include "lldb/Core/DataBuffer.h"
16 #include "lldb/Core/DataBufferHeap.h"
17 #include "lldb/Core/Debugger.h"
18 #include "lldb/Core/Log.h"
19 #include "lldb/Core/Module.h"
20 #include "lldb/Core/ModuleSpec.h"
21 #include "lldb/Core/PluginManager.h"
22 #include "lldb/Core/Section.h"
23 #include "lldb/Core/State.h"
24 #include "lldb/Core/StreamFile.h"
25 #include "lldb/Host/Symbols.h"
26 #include "lldb/Interpreter/OptionValueProperties.h"
27 #include "lldb/Symbol/ObjectFile.h"
28 #include "lldb/Target/RegisterContext.h"
29 #include "lldb/Target/StackFrame.h"
30 #include "lldb/Target/Target.h"
31 #include "lldb/Target/Thread.h"
32 #include "lldb/Target/ThreadPlanRunToAddress.h"
33 #include "Plugins/Platform/MacOSX/PlatformDarwinKernel.h"
34 
35 #include "DynamicLoaderDarwinKernel.h"
36 
37 //#define ENABLE_DEBUG_PRINTF // COMMENT THIS LINE OUT PRIOR TO CHECKIN
38 #ifdef ENABLE_DEBUG_PRINTF
39 #include <stdio.h>
40 #define DEBUG_PRINTF(fmt, ...) printf(fmt, ## __VA_ARGS__)
41 #else
42 #define DEBUG_PRINTF(fmt, ...)
43 #endif
44 
45 using namespace lldb;
46 using namespace lldb_private;
47 
48 // Progressively greater amounts of scanning we will allow
49 // For some targets very early in startup, we can't do any random reads of memory or we can crash the device
50 // so a setting is needed that can completely disable the KASLR scans.
51 
52 enum KASLRScanType
53 {
54     eKASLRScanNone = 0,         // No reading into the inferior at all
55     eKASLRScanLowgloAddresses,  // Check one word of memory for a possible kernel addr, then see if a kernel is there
56     eKASLRScanNearPC,           // Scan backwards from the current $pc looking for kernel; checking at 96 locations total
57     eKASLRScanExhaustiveScan    // Scan through the entire possible kernel address range looking for a kernel
58 };
59 
60 OptionEnumValueElement
61 g_kaslr_kernel_scan_enum_values[] =
62 {
63     { eKASLRScanNone,            "none",            "Do not read memory looking for a Darwin kernel when attaching." },
64     { eKASLRScanLowgloAddresses, "basic",           "Check for the Darwin kernel's load addr in the lowglo page (boot-args=debug) only." },
65     { eKASLRScanNearPC,          "fast-scan",       "Scan near the pc value on attach to find the Darwin kernel's load address."},
66     { eKASLRScanExhaustiveScan,  "exhaustive-scan", "Scan through the entire potential address range of Darwin kernel (only on 32-bit targets)."},
67     { 0, NULL, NULL }
68 };
69 
70 static PropertyDefinition
71 g_properties[] =
72 {
73     { "load-kexts" , OptionValue::eTypeBoolean, true, true, NULL, NULL, "Automatically loads kext images when attaching to a kernel." },
74     { "scan-type",   OptionValue::eTypeEnum,    true, eKASLRScanNearPC, NULL, g_kaslr_kernel_scan_enum_values, "Control how many reads lldb will make while searching for a Darwin kernel on attach." },
75     {  NULL        , OptionValue::eTypeInvalid, false, 0  , NULL, NULL, NULL  }
76 };
77 
78 enum {
79     ePropertyLoadKexts,
80     ePropertyScanType
81 };
82 
83 class DynamicLoaderDarwinKernelProperties : public Properties
84 {
85 public:
86 
87     static ConstString &
88     GetSettingName ()
89     {
90         static ConstString g_setting_name("darwin-kernel");
91         return g_setting_name;
92     }
93 
94     DynamicLoaderDarwinKernelProperties() :
95         Properties ()
96     {
97         m_collection_sp.reset (new OptionValueProperties(GetSettingName()));
98         m_collection_sp->Initialize(g_properties);
99     }
100 
101     virtual
102     ~DynamicLoaderDarwinKernelProperties()
103     {
104     }
105 
106     bool
107     GetLoadKexts() const
108     {
109         const uint32_t idx = ePropertyLoadKexts;
110         return m_collection_sp->GetPropertyAtIndexAsBoolean (NULL, idx, g_properties[idx].default_uint_value != 0);
111     }
112 
113     KASLRScanType
114     GetScanType() const
115     {
116         const uint32_t idx = ePropertyScanType;
117         return (KASLRScanType) m_collection_sp->GetPropertyAtIndexAsEnumeration (NULL, idx, g_properties[idx].default_uint_value);
118     }
119 
120 
121 };
122 
123 typedef std::shared_ptr<DynamicLoaderDarwinKernelProperties> DynamicLoaderDarwinKernelPropertiesSP;
124 
125 static const DynamicLoaderDarwinKernelPropertiesSP &
126 GetGlobalProperties()
127 {
128     static DynamicLoaderDarwinKernelPropertiesSP g_settings_sp;
129     if (!g_settings_sp)
130         g_settings_sp.reset (new DynamicLoaderDarwinKernelProperties ());
131     return g_settings_sp;
132 }
133 
134 //----------------------------------------------------------------------
135 // Create an instance of this class. This function is filled into
136 // the plugin info class that gets handed out by the plugin factory and
137 // allows the lldb to instantiate an instance of this class.
138 //----------------------------------------------------------------------
139 DynamicLoader *
140 DynamicLoaderDarwinKernel::CreateInstance (Process* process, bool force)
141 {
142     if (!force)
143     {
144         // If the user provided an executable binary and it is not a kernel,
145         // this plugin should not create an instance.
146         Module* exe_module = process->GetTarget().GetExecutableModulePointer();
147         if (exe_module)
148         {
149             ObjectFile *object_file = exe_module->GetObjectFile();
150             if (object_file)
151             {
152                 if (object_file->GetStrata() != ObjectFile::eStrataKernel)
153                 {
154                     return NULL;
155                 }
156             }
157         }
158 
159         // If the target's architecture does not look like an Apple environment,
160         // this plugin should not create an instance.
161         const llvm::Triple &triple_ref = process->GetTarget().GetArchitecture().GetTriple();
162         switch (triple_ref.getOS())
163         {
164             case llvm::Triple::Darwin:
165             case llvm::Triple::MacOSX:
166             case llvm::Triple::IOS:
167                 if (triple_ref.getVendor() != llvm::Triple::Apple)
168                 {
169                    return NULL;
170                 }
171                 break;
172             // If we have triple like armv7-unknown-unknown, we should try looking for a Darwin kernel.
173             case llvm::Triple::UnknownOS:
174                 break;
175             default:
176                 return NULL;
177                 break;
178         }
179     }
180 
181     // At this point if there is an ExecutableModule, it is a kernel and the Target is some variant of an Apple system.
182     // If the Process hasn't provided the kernel load address, we need to look around in memory to find it.
183 
184     addr_t kernel_load_address = SearchForDarwinKernel (process);
185     if (kernel_load_address != LLDB_INVALID_ADDRESS)
186     {
187         process->SetCanJIT(false);
188         return new DynamicLoaderDarwinKernel (process, kernel_load_address);
189     }
190     return NULL;
191 }
192 
193 lldb::addr_t
194 DynamicLoaderDarwinKernel::SearchForDarwinKernel (Process *process)
195 {
196     addr_t kernel_load_address = process->GetImageInfoAddress();
197     if (kernel_load_address == LLDB_INVALID_ADDRESS)
198     {
199         kernel_load_address = SearchForKernelAtSameLoadAddr (process);
200         if (kernel_load_address == LLDB_INVALID_ADDRESS)
201         {
202             kernel_load_address = SearchForKernelWithDebugHints (process);
203             if (kernel_load_address == LLDB_INVALID_ADDRESS)
204             {
205                 kernel_load_address = SearchForKernelNearPC (process);
206                 if (kernel_load_address == LLDB_INVALID_ADDRESS)
207                 {
208                     kernel_load_address = SearchForKernelViaExhaustiveSearch (process);
209                 }
210             }
211         }
212     }
213     return kernel_load_address;
214 }
215 
216 //----------------------------------------------------------------------
217 // Check if the kernel binary is loaded in memory without a slide.
218 // First verify that the ExecutableModule is a kernel before we proceed.
219 // Returns the address of the kernel if one was found, else LLDB_INVALID_ADDRESS.
220 //----------------------------------------------------------------------
221 lldb::addr_t
222 DynamicLoaderDarwinKernel::SearchForKernelAtSameLoadAddr (Process *process)
223 {
224     Module *exe_module = process->GetTarget().GetExecutableModulePointer();
225     if (exe_module == NULL)
226         return LLDB_INVALID_ADDRESS;
227 
228     ObjectFile *exe_objfile = exe_module->GetObjectFile();
229     if (exe_objfile == NULL)
230         return LLDB_INVALID_ADDRESS;
231 
232     if (exe_objfile->GetType() != ObjectFile::eTypeExecutable || exe_objfile->GetStrata() != ObjectFile::eStrataKernel)
233         return LLDB_INVALID_ADDRESS;
234 
235     if (!exe_objfile->GetHeaderAddress().IsValid())
236         return LLDB_INVALID_ADDRESS;
237 
238     if (CheckForKernelImageAtAddress (exe_objfile->GetHeaderAddress().GetFileAddress(), process) == exe_module->GetUUID())
239         return exe_objfile->GetHeaderAddress().GetFileAddress();
240 
241     return LLDB_INVALID_ADDRESS;
242 }
243 
244 //----------------------------------------------------------------------
245 // If the debug flag is included in the boot-args nvram setting, the kernel's load address
246 // will be noted in the lowglo page at a fixed address
247 // Returns the address of the kernel if one was found, else LLDB_INVALID_ADDRESS.
248 //----------------------------------------------------------------------
249 lldb::addr_t
250 DynamicLoaderDarwinKernel::SearchForKernelWithDebugHints (Process *process)
251 {
252     if (GetGlobalProperties()->GetScanType() == eKASLRScanNone)
253         return LLDB_INVALID_ADDRESS;
254 
255     Error read_err;
256     addr_t addr = LLDB_INVALID_ADDRESS;
257     if (process->GetTarget().GetArchitecture().GetAddressByteSize() == 8)
258     {
259         addr = process->ReadUnsignedIntegerFromMemory (0xffffff8000002010ULL, 8, LLDB_INVALID_ADDRESS, read_err);
260         if (CheckForKernelImageAtAddress (addr, process).IsValid())
261         {
262             return addr;
263         }
264         addr = process->ReadUnsignedIntegerFromMemory (0xffffff8000004010ULL, 8, LLDB_INVALID_ADDRESS, read_err);
265         if (CheckForKernelImageAtAddress (addr, process).IsValid())
266         {
267             return addr;
268         }
269     }
270     else
271     {
272         addr = process->ReadUnsignedIntegerFromMemory (0xffff0110, 4, LLDB_INVALID_ADDRESS, read_err);
273         if (CheckForKernelImageAtAddress (addr, process).IsValid())
274         {
275             return addr;
276         }
277     }
278     return LLDB_INVALID_ADDRESS;
279 }
280 
281 //----------------------------------------------------------------------
282 // If the kernel is currently executing when lldb attaches, and we don't have
283 // a better way of finding the kernel's load address, try searching backwards
284 // from the current pc value looking for the kernel's Mach header in memory.
285 // Returns the address of the kernel if one was found, else LLDB_INVALID_ADDRESS.
286 //----------------------------------------------------------------------
287 lldb::addr_t
288 DynamicLoaderDarwinKernel::SearchForKernelNearPC (Process *process)
289 {
290     if (GetGlobalProperties()->GetScanType() == eKASLRScanNone
291         || GetGlobalProperties()->GetScanType() == eKASLRScanLowgloAddresses)
292     {
293         return LLDB_INVALID_ADDRESS;
294     }
295 
296     ThreadSP thread = process->GetThreadList().GetSelectedThread ();
297     if (thread.get() == NULL)
298         return LLDB_INVALID_ADDRESS;
299     addr_t pc = thread->GetRegisterContext ()->GetPC(LLDB_INVALID_ADDRESS);
300 
301     if (pc == LLDB_INVALID_ADDRESS)
302         return LLDB_INVALID_ADDRESS;
303 
304     addr_t kernel_range_low;
305     if (process->GetTarget().GetArchitecture().GetAddressByteSize() == 8)
306     {
307         kernel_range_low = 1ULL << 63;
308     }
309     else
310     {
311         kernel_range_low = 1ULL << 31;
312     }
313 
314     // Outside the normal kernel address range, this is probably userland code running right now
315     if (pc < kernel_range_low)
316         return LLDB_INVALID_ADDRESS;
317 
318     // The kernel will load at at one megabyte boundary (0x100000), or at that boundary plus
319     // an offset of one page (0x1000) or two, depending on the device.
320 
321     // Round the current pc down to the nearest one megabyte boundary - the place where we will start searching.
322     addr_t addr = pc & ~0xfffff;
323 
324     int i = 0;
325     while (i < 32 && pc >= kernel_range_low)
326     {
327         if (CheckForKernelImageAtAddress (addr, process).IsValid())
328             return addr;
329         if (CheckForKernelImageAtAddress (addr + 0x1000, process).IsValid())
330             return addr + 0x1000;
331         if (CheckForKernelImageAtAddress (addr + 0x2000, process).IsValid())
332             return addr + 0x2000;
333         if (CheckForKernelImageAtAddress (addr + 0x4000, process).IsValid())
334             return addr + 0x4000;
335         i++;
336         addr -= 0x100000;
337     }
338 
339     return LLDB_INVALID_ADDRESS;
340 }
341 
342 //----------------------------------------------------------------------
343 // Scan through the valid address range for a kernel binary.
344 // This is uselessly slow in 64-bit environments so we don't even try it.
345 // This scan is not enabled by default even for 32-bit targets.
346 // Returns the address of the kernel if one was found, else LLDB_INVALID_ADDRESS.
347 //----------------------------------------------------------------------
348 lldb::addr_t
349 DynamicLoaderDarwinKernel::SearchForKernelViaExhaustiveSearch (Process *process)
350 {
351     if (GetGlobalProperties()->GetScanType() != eKASLRScanExhaustiveScan)
352     {
353         return LLDB_INVALID_ADDRESS;
354     }
355 
356     addr_t kernel_range_low, kernel_range_high;
357     if (process->GetTarget().GetArchitecture().GetAddressByteSize() == 8)
358     {
359         kernel_range_low = 1ULL << 63;
360         kernel_range_high = UINT64_MAX;
361     }
362     else
363     {
364         kernel_range_low = 1ULL << 31;
365         kernel_range_high = UINT32_MAX;
366     }
367 
368     // Stepping through memory at one-megabyte resolution looking for a kernel
369     // rarely works (fast enough) with a 64-bit address space -- for now, let's
370     // not even bother.  We may be attaching to something which *isn't* a kernel
371     // and we don't want to spin for minutes on-end looking for a kernel.
372     if (process->GetTarget().GetArchitecture().GetAddressByteSize() == 8)
373         return LLDB_INVALID_ADDRESS;
374 
375     addr_t addr = kernel_range_low;
376 
377     while (addr >= kernel_range_low && addr < kernel_range_high)
378     {
379         if (CheckForKernelImageAtAddress (addr, process).IsValid())
380             return addr;
381         if (CheckForKernelImageAtAddress (addr + 0x1000, process).IsValid())
382             return addr + 0x1000;
383         if (CheckForKernelImageAtAddress (addr + 0x2000, process).IsValid())
384             return addr + 0x2000;
385         if (CheckForKernelImageAtAddress (addr + 0x4000, process).IsValid())
386             return addr + 0x4000;
387         addr += 0x100000;
388     }
389     return LLDB_INVALID_ADDRESS;
390 }
391 
392 //----------------------------------------------------------------------
393 // Given an address in memory, look to see if there is a kernel image at that
394 // address.
395 // Returns a UUID; if a kernel was not found at that address, UUID.IsValid() will be false.
396 //----------------------------------------------------------------------
397 lldb_private::UUID
398 DynamicLoaderDarwinKernel::CheckForKernelImageAtAddress (lldb::addr_t addr, Process *process)
399 {
400     if (addr == LLDB_INVALID_ADDRESS)
401         return UUID();
402 
403     // First try a quick test -- read the first 4 bytes and see if there is a valid Mach-O magic field there
404     // (the first field of the mach_header/mach_header_64 struct).
405 
406     Error read_error;
407     uint64_t result = process->ReadUnsignedIntegerFromMemory (addr, 4, LLDB_INVALID_ADDRESS, read_error);
408     if (result != llvm::MachO::MH_MAGIC_64
409         && result != llvm::MachO::MH_MAGIC
410         && result != llvm::MachO::MH_CIGAM
411         && result != llvm::MachO::MH_CIGAM_64)
412     {
413         return UUID();
414     }
415 
416     // Read the mach header and see whether it looks like a kernel
417     llvm::MachO::mach_header header;
418     if (process->DoReadMemory (addr, &header, sizeof(header), read_error) != sizeof(header))
419         return UUID();
420 
421     if (header.magic == llvm::MachO::MH_CIGAM ||
422         header.magic == llvm::MachO::MH_CIGAM_64)
423     {
424         header.magic        = llvm::ByteSwap_32(header.magic);
425         header.cputype      = llvm::ByteSwap_32(header.cputype);
426         header.cpusubtype   = llvm::ByteSwap_32(header.cpusubtype);
427         header.filetype     = llvm::ByteSwap_32(header.filetype);
428         header.ncmds        = llvm::ByteSwap_32(header.ncmds);
429         header.sizeofcmds   = llvm::ByteSwap_32(header.sizeofcmds);
430         header.flags        = llvm::ByteSwap_32(header.flags);
431     }
432 
433     // A kernel is an executable which does not have the dynamic link object flag set.
434     if (header.filetype == llvm::MachO::MH_EXECUTE
435         && (header.flags & llvm::MachO::MH_DYLDLINK) == 0)
436     {
437         // Create a full module to get the UUID
438         ModuleSP memory_module_sp = process->ReadModuleFromMemory (FileSpec ("temp_mach_kernel", false), addr);
439         if (!memory_module_sp.get())
440             return UUID();
441 
442         ObjectFile *exe_objfile = memory_module_sp->GetObjectFile();
443         if (exe_objfile == NULL)
444             return UUID();
445 
446         if (exe_objfile->GetType() == ObjectFile::eTypeExecutable && exe_objfile->GetStrata() == ObjectFile::eStrataKernel)
447         {
448             ArchSpec kernel_arch (eArchTypeMachO, header.cputype, header.cpusubtype);
449             if (!process->GetTarget().GetArchitecture().IsCompatibleMatch(kernel_arch))
450             {
451                 process->GetTarget().SetArchitecture (kernel_arch);
452             }
453             return memory_module_sp->GetUUID();
454         }
455     }
456 
457     return UUID();
458 }
459 
460 //----------------------------------------------------------------------
461 // Constructor
462 //----------------------------------------------------------------------
463 DynamicLoaderDarwinKernel::DynamicLoaderDarwinKernel (Process* process, lldb::addr_t kernel_addr) :
464     DynamicLoader(process),
465     m_kernel_load_address (kernel_addr),
466     m_kernel(),
467     m_kext_summary_header_ptr_addr (),
468     m_kext_summary_header_addr (),
469     m_kext_summary_header (),
470     m_known_kexts (),
471     m_mutex(Mutex::eMutexTypeRecursive),
472     m_break_id (LLDB_INVALID_BREAK_ID)
473 {
474     Error error;
475     PlatformSP platform_sp(Platform::Create(PlatformDarwinKernel::GetPluginNameStatic(), error));
476     // Only select the darwin-kernel Platform if we've been asked to load kexts.
477     // It can take some time to scan over all of the kext info.plists and that
478     // shouldn't be done if kext loading is explicitly disabled.
479     if (platform_sp.get() && GetGlobalProperties()->GetLoadKexts())
480     {
481         process->GetTarget().SetPlatform (platform_sp);
482     }
483 }
484 
485 //----------------------------------------------------------------------
486 // Destructor
487 //----------------------------------------------------------------------
488 DynamicLoaderDarwinKernel::~DynamicLoaderDarwinKernel()
489 {
490     Clear(true);
491 }
492 
493 void
494 DynamicLoaderDarwinKernel::UpdateIfNeeded()
495 {
496     LoadKernelModuleIfNeeded();
497     SetNotificationBreakpointIfNeeded ();
498 }
499 //------------------------------------------------------------------
500 /// Called after attaching a process.
501 ///
502 /// Allow DynamicLoader plug-ins to execute some code after
503 /// attaching to a process.
504 //------------------------------------------------------------------
505 void
506 DynamicLoaderDarwinKernel::DidAttach ()
507 {
508     PrivateInitialize(m_process);
509     UpdateIfNeeded();
510 }
511 
512 //------------------------------------------------------------------
513 /// Called after attaching a process.
514 ///
515 /// Allow DynamicLoader plug-ins to execute some code after
516 /// attaching to a process.
517 //------------------------------------------------------------------
518 void
519 DynamicLoaderDarwinKernel::DidLaunch ()
520 {
521     PrivateInitialize(m_process);
522     UpdateIfNeeded();
523 }
524 
525 
526 //----------------------------------------------------------------------
527 // Clear out the state of this class.
528 //----------------------------------------------------------------------
529 void
530 DynamicLoaderDarwinKernel::Clear (bool clear_process)
531 {
532     Mutex::Locker locker(m_mutex);
533 
534     if (m_process->IsAlive() && LLDB_BREAK_ID_IS_VALID(m_break_id))
535         m_process->ClearBreakpointSiteByID(m_break_id);
536 
537     if (clear_process)
538         m_process = NULL;
539     m_kernel.Clear();
540     m_known_kexts.clear();
541     m_kext_summary_header_ptr_addr.Clear();
542     m_kext_summary_header_addr.Clear();
543     m_break_id = LLDB_INVALID_BREAK_ID;
544 }
545 
546 
547 bool
548 DynamicLoaderDarwinKernel::KextImageInfo::LoadImageAtFileAddress (Process *process)
549 {
550     if (IsLoaded())
551         return true;
552 
553     if (m_module_sp)
554     {
555         bool changed = false;
556         if (m_module_sp->SetLoadAddress (process->GetTarget(), 0, true, changed))
557             m_load_process_stop_id = process->GetStopID();
558     }
559     return false;
560 }
561 
562 void
563 DynamicLoaderDarwinKernel::KextImageInfo::SetModule (ModuleSP module_sp)
564 {
565     m_module_sp = module_sp;
566     if (module_sp.get() && module_sp->GetObjectFile())
567     {
568         if (module_sp->GetObjectFile()->GetType() == ObjectFile::eTypeExecutable
569             && module_sp->GetObjectFile()->GetStrata() == ObjectFile::eStrataKernel)
570         {
571             m_kernel_image = true;
572         }
573         else
574         {
575             m_kernel_image = false;
576         }
577     }
578 }
579 
580 ModuleSP
581 DynamicLoaderDarwinKernel::KextImageInfo::GetModule ()
582 {
583     return m_module_sp;
584 }
585 
586 void
587 DynamicLoaderDarwinKernel::KextImageInfo::SetLoadAddress (addr_t load_addr)
588 {
589     m_load_address = load_addr;
590 }
591 
592 addr_t
593 DynamicLoaderDarwinKernel::KextImageInfo::GetLoadAddress () const
594 {
595     return m_load_address;
596 }
597 
598 uint64_t
599 DynamicLoaderDarwinKernel::KextImageInfo::GetSize () const
600 {
601     return m_size;
602 }
603 
604 void
605 DynamicLoaderDarwinKernel::KextImageInfo::SetSize (uint64_t size)
606 {
607     m_size = size;
608 }
609 
610 uint32_t
611 DynamicLoaderDarwinKernel::KextImageInfo::GetProcessStopId () const
612 {
613     return m_load_process_stop_id;
614 }
615 
616 void
617 DynamicLoaderDarwinKernel::KextImageInfo::SetProcessStopId (uint32_t stop_id)
618 {
619     m_load_process_stop_id = stop_id;
620 }
621 
622 bool
623 DynamicLoaderDarwinKernel::KextImageInfo::operator== (const KextImageInfo &rhs)
624 {
625     if (m_uuid.IsValid() || rhs.GetUUID().IsValid())
626     {
627         if (m_uuid == rhs.GetUUID())
628         {
629             return true;
630         }
631         return false;
632     }
633 
634     if (m_name == rhs.GetName() && m_load_address == rhs.GetLoadAddress())
635         return true;
636 
637     return false;
638 }
639 
640 void
641 DynamicLoaderDarwinKernel::KextImageInfo::SetName (const char *name)
642 {
643     m_name = name;
644 }
645 
646 std::string
647 DynamicLoaderDarwinKernel::KextImageInfo::GetName () const
648 {
649     return m_name;
650 }
651 
652 void
653 DynamicLoaderDarwinKernel::KextImageInfo::SetUUID (const UUID &uuid)
654 {
655     m_uuid = uuid;
656 }
657 
658 UUID
659 DynamicLoaderDarwinKernel::KextImageInfo::GetUUID () const
660 {
661     return m_uuid;
662 }
663 
664 // Given the m_load_address from the kext summaries, and a UUID, try to create an in-memory
665 // Module at that address.  Require that the MemoryModule have a matching UUID and detect
666 // if this MemoryModule is a kernel or a kext.
667 //
668 // Returns true if m_memory_module_sp is now set to a valid Module.
669 
670 bool
671 DynamicLoaderDarwinKernel::KextImageInfo::ReadMemoryModule (Process *process)
672 {
673     if (m_memory_module_sp.get() != NULL)
674         return true;
675     if (m_load_address == LLDB_INVALID_ADDRESS)
676         return false;
677 
678     FileSpec file_spec;
679     file_spec.SetFile (m_name.c_str(), false);
680 
681     ModuleSP memory_module_sp = process->ReadModuleFromMemory (file_spec, m_load_address);
682 
683     if (memory_module_sp.get() == NULL)
684         return false;
685 
686     bool is_kernel = false;
687     if (memory_module_sp->GetObjectFile())
688     {
689         if (memory_module_sp->GetObjectFile()->GetType() == ObjectFile::eTypeExecutable
690             && memory_module_sp->GetObjectFile()->GetStrata() == ObjectFile::eStrataKernel)
691         {
692             is_kernel = true;
693         }
694         else if (memory_module_sp->GetObjectFile()->GetType() == ObjectFile::eTypeSharedLibrary)
695         {
696             is_kernel = false;
697         }
698     }
699 
700     // If this is a kext, and the kernel specified what UUID we should find at this
701     // load address, require that the memory module have a matching UUID or something
702     // has gone wrong and we should discard it.
703     if (m_uuid.IsValid())
704     {
705         if (m_uuid != memory_module_sp->GetUUID())
706         {
707             return false;
708         }
709     }
710 
711     // If the in-memory Module has a UUID, let's use that.
712     if (!m_uuid.IsValid() && memory_module_sp->GetUUID().IsValid())
713     {
714         m_uuid = memory_module_sp->GetUUID();
715     }
716 
717     m_memory_module_sp = memory_module_sp;
718     m_kernel_image = is_kernel;
719     if (is_kernel)
720     {
721         if (memory_module_sp->GetArchitecture().IsValid())
722         {
723             process->GetTarget().SetArchitecture(memory_module_sp->GetArchitecture());
724         }
725         if (m_uuid.IsValid())
726         {
727             Module* exe_module = process->GetTarget().GetExecutableModulePointer();
728             if (exe_module && exe_module->GetUUID().IsValid())
729             {
730                 if (m_uuid != exe_module->GetUUID())
731                 {
732                     Stream *s = process->GetTarget().GetDebugger().GetOutputFile().get();
733                     if (s)
734                     {
735                         s->Printf ("warning: Host-side kernel file has Mach-O UUID of %s but remote kernel has a UUID of %s -- a mismatched kernel file will result in a poor debugger experience.\n",
736                                    exe_module->GetUUID().GetAsString().c_str(),
737                                    m_uuid.GetAsString().c_str());
738                         s->Flush ();
739                     }
740                 }
741             }
742         }
743     }
744 
745     return true;
746 }
747 
748 bool
749 DynamicLoaderDarwinKernel::KextImageInfo::IsKernel () const
750 {
751     return m_kernel_image == true;
752 }
753 
754 void
755 DynamicLoaderDarwinKernel::KextImageInfo::SetIsKernel (bool is_kernel)
756 {
757     m_kernel_image = is_kernel;
758 }
759 
760 bool
761 DynamicLoaderDarwinKernel::KextImageInfo::LoadImageUsingMemoryModule (Process *process)
762 {
763     if (IsLoaded())
764         return true;
765 
766 
767     Target &target = process->GetTarget();
768 
769     // If we don't have / can't create a memory module for this kext, don't try to load it - we won't
770     // have the correct segment load addresses.
771     if (!ReadMemoryModule (process))
772     {
773         return false;
774     }
775 
776     bool uuid_is_valid = m_uuid.IsValid();
777 
778     if (IsKernel() && uuid_is_valid && m_memory_module_sp.get())
779     {
780         Stream *s = target.GetDebugger().GetOutputFile().get();
781         if (s)
782         {
783             s->Printf ("Kernel UUID: %s\n", m_memory_module_sp->GetUUID().GetAsString().c_str());
784             s->Printf ("Load Address: 0x%" PRIx64 "\n", m_load_address);
785         }
786     }
787 
788     if (!m_module_sp)
789     {
790         // See if the kext has already been loaded into the target, probably by the user doing target modules add.
791         const ModuleList &target_images = target.GetImages();
792         m_module_sp = target_images.FindModule(m_uuid);
793 
794         // Search for the kext on the local filesystem via the UUID
795         if (!m_module_sp && uuid_is_valid)
796         {
797             ModuleSpec module_spec;
798             module_spec.GetUUID() = m_uuid;
799             module_spec.GetArchitecture() = target.GetArchitecture();
800 
801             // For the kernel, we really do need an on-disk file copy of the binary to do anything useful.
802             // This will force a clal to
803             if (IsKernel())
804             {
805                 if (Symbols::DownloadObjectAndSymbolFile (module_spec, true))
806                 {
807                     if (module_spec.GetFileSpec().Exists())
808                     {
809                         m_module_sp.reset(new Module (module_spec.GetFileSpec(), target.GetArchitecture()));
810                         if (m_module_sp.get() && m_module_sp->MatchesModuleSpec (module_spec))
811                         {
812                             ModuleList loaded_module_list;
813                             loaded_module_list.Append (m_module_sp);
814                             target.ModulesDidLoad (loaded_module_list);
815                         }
816                     }
817                 }
818             }
819 
820             // If the current platform is PlatformDarwinKernel, create a ModuleSpec with the filename set
821             // to be the bundle ID for this kext, e.g. "com.apple.filesystems.msdosfs", and ask the platform
822             // to find it.
823             PlatformSP platform_sp (target.GetPlatform());
824             if (!m_module_sp && platform_sp)
825             {
826                 ConstString platform_name (platform_sp->GetPluginName());
827                 static ConstString g_platform_name (PlatformDarwinKernel::GetPluginNameStatic());
828                 if (platform_name == g_platform_name)
829                 {
830                     ModuleSpec kext_bundle_module_spec(module_spec);
831                     FileSpec kext_filespec(m_name.c_str(), false);
832                     kext_bundle_module_spec.GetFileSpec() = kext_filespec;
833                     platform_sp->GetSharedModule (kext_bundle_module_spec, m_module_sp, &target.GetExecutableSearchPaths(), NULL, NULL);
834                 }
835             }
836 
837             // Ask the Target to find this file on the local system, if possible.
838             // This will search in the list of currently-loaded files, look in the
839             // standard search paths on the system, and on a Mac it will try calling
840             // the DebugSymbols framework with the UUID to find the binary via its
841             // search methods.
842             if (!m_module_sp)
843             {
844                 m_module_sp = target.GetSharedModule (module_spec);
845             }
846 
847             if (IsKernel() && !m_module_sp)
848             {
849                 Stream *s = target.GetDebugger().GetOutputFile().get();
850                 if (s)
851                 {
852                     s->Printf ("WARNING: Unable to locate kernel binary on the debugger system.\n");
853                 }
854             }
855         }
856 
857         // If we managed to find a module, append it to the target's list of images.
858         // If we also have a memory module, require that they have matching UUIDs
859         if (m_module_sp)
860         {
861             bool uuid_match_ok = true;
862             if (m_memory_module_sp)
863             {
864                 if (m_module_sp->GetUUID() != m_memory_module_sp->GetUUID())
865                 {
866                     uuid_match_ok = false;
867                 }
868             }
869             if (uuid_match_ok)
870             {
871                 target.GetImages().AppendIfNeeded(m_module_sp);
872                 if (IsKernel() && target.GetExecutableModulePointer() != m_module_sp.get())
873                 {
874                     target.SetExecutableModule (m_module_sp, false);
875                 }
876             }
877         }
878     }
879 
880     if (!m_module_sp && !IsKernel() && m_uuid.IsValid() && !m_name.empty())
881     {
882         Stream *s = target.GetDebugger().GetOutputFile().get();
883         if (s)
884         {
885             s->Printf ("warning: Can't find binary/dSYM for %s (%s)\n",
886                        m_name.c_str(), m_uuid.GetAsString().c_str());
887         }
888     }
889 
890     static ConstString g_section_name_LINKEDIT ("__LINKEDIT");
891 
892     if (m_memory_module_sp && m_module_sp)
893     {
894         if (m_module_sp->GetUUID() == m_memory_module_sp->GetUUID())
895         {
896             ObjectFile *ondisk_object_file = m_module_sp->GetObjectFile();
897             ObjectFile *memory_object_file = m_memory_module_sp->GetObjectFile();
898 
899             if (memory_object_file && ondisk_object_file)
900             {
901                 // The memory_module for kexts may have an invalid __LINKEDIT seg; skip it.
902                 const bool ignore_linkedit = !IsKernel ();
903 
904                 SectionList *ondisk_section_list = ondisk_object_file->GetSectionList ();
905                 SectionList *memory_section_list = memory_object_file->GetSectionList ();
906                 if (memory_section_list && ondisk_section_list)
907                 {
908                     const uint32_t num_ondisk_sections = ondisk_section_list->GetSize();
909                     // There may be CTF sections in the memory image so we can't
910                     // always just compare the number of sections (which are actually
911                     // segments in mach-o parlance)
912                     uint32_t sect_idx = 0;
913 
914                     // Use the memory_module's addresses for each section to set the
915                     // file module's load address as appropriate.  We don't want to use
916                     // a single slide value for the entire kext - different segments may
917                     // be slid different amounts by the kext loader.
918 
919                     uint32_t num_sections_loaded = 0;
920                     for (sect_idx=0; sect_idx<num_ondisk_sections; ++sect_idx)
921                     {
922                         SectionSP ondisk_section_sp(ondisk_section_list->GetSectionAtIndex(sect_idx));
923                         if (ondisk_section_sp)
924                         {
925                             // Don't ever load __LINKEDIT as it may or may not be actually
926                             // mapped into memory and there is no current way to tell.
927                             // I filed rdar://problem/12851706 to track being able to tell
928                             // if the __LINKEDIT is actually mapped, but until then, we need
929                             // to not load the __LINKEDIT
930                             if (ignore_linkedit && ondisk_section_sp->GetName() == g_section_name_LINKEDIT)
931                                 continue;
932 
933                             const Section *memory_section = memory_section_list->FindSectionByName(ondisk_section_sp->GetName()).get();
934                             if (memory_section)
935                             {
936                                 target.SetSectionLoadAddress (ondisk_section_sp, memory_section->GetFileAddress());
937                                 ++num_sections_loaded;
938                             }
939                         }
940                     }
941                     if (num_sections_loaded > 0)
942                         m_load_process_stop_id = process->GetStopID();
943                     else
944                         m_module_sp.reset(); // No sections were loaded
945                 }
946                 else
947                     m_module_sp.reset(); // One or both section lists
948             }
949             else
950                 m_module_sp.reset(); // One or both object files missing
951         }
952         else
953             m_module_sp.reset(); // UUID mismatch
954     }
955 
956     bool is_loaded = IsLoaded();
957 
958     if (is_loaded && m_module_sp && IsKernel())
959     {
960         Stream *s = target.GetDebugger().GetOutputFile().get();
961         if (s)
962         {
963             ObjectFile *kernel_object_file = m_module_sp->GetObjectFile();
964             if (kernel_object_file)
965             {
966                 addr_t file_address = kernel_object_file->GetHeaderAddress().GetFileAddress();
967                 if (m_load_address != LLDB_INVALID_ADDRESS && file_address != LLDB_INVALID_ADDRESS)
968                 {
969                     s->Printf ("Kernel slid 0x%" PRIx64 " in memory.\n", m_load_address - file_address);
970                 }
971             }
972             {
973                 s->Printf ("Loaded kernel file %s\n",
974                            m_module_sp->GetFileSpec().GetPath().c_str());
975             }
976             s->Flush ();
977         }
978     }
979     return is_loaded;
980 }
981 
982 uint32_t
983 DynamicLoaderDarwinKernel::KextImageInfo::GetAddressByteSize ()
984 {
985     if (m_memory_module_sp)
986         return m_memory_module_sp->GetArchitecture().GetAddressByteSize();
987     if (m_module_sp)
988         return m_module_sp->GetArchitecture().GetAddressByteSize();
989     return 0;
990 }
991 
992 lldb::ByteOrder
993 DynamicLoaderDarwinKernel::KextImageInfo::GetByteOrder()
994 {
995     if (m_memory_module_sp)
996         return m_memory_module_sp->GetArchitecture().GetByteOrder();
997     if (m_module_sp)
998         return m_module_sp->GetArchitecture().GetByteOrder();
999     return lldb::endian::InlHostByteOrder();
1000 }
1001 
1002 lldb_private::ArchSpec
1003 DynamicLoaderDarwinKernel::KextImageInfo::GetArchitecture () const
1004 {
1005     if (m_memory_module_sp)
1006         return m_memory_module_sp->GetArchitecture();
1007     if (m_module_sp)
1008         return m_module_sp->GetArchitecture();
1009     return lldb_private::ArchSpec ();
1010 }
1011 
1012 
1013 //----------------------------------------------------------------------
1014 // Load the kernel module and initialize the "m_kernel" member. Return
1015 // true _only_ if the kernel is loaded the first time through (subsequent
1016 // calls to this function should return false after the kernel has been
1017 // already loaded).
1018 //----------------------------------------------------------------------
1019 void
1020 DynamicLoaderDarwinKernel::LoadKernelModuleIfNeeded()
1021 {
1022     if (!m_kext_summary_header_ptr_addr.IsValid())
1023     {
1024         m_kernel.Clear();
1025         m_kernel.SetModule (m_process->GetTarget().GetExecutableModule());
1026         m_kernel.SetIsKernel(true);
1027 
1028         ConstString kernel_name("mach_kernel");
1029         if (m_kernel.GetModule().get()
1030             && m_kernel.GetModule()->GetObjectFile()
1031             && !m_kernel.GetModule()->GetObjectFile()->GetFileSpec().GetFilename().IsEmpty())
1032         {
1033             kernel_name = m_kernel.GetModule()->GetObjectFile()->GetFileSpec().GetFilename();
1034         }
1035         m_kernel.SetName (kernel_name.AsCString());
1036 
1037         if (m_kernel.GetLoadAddress() == LLDB_INVALID_ADDRESS)
1038         {
1039             m_kernel.SetLoadAddress(m_kernel_load_address);
1040             if (m_kernel.GetLoadAddress() == LLDB_INVALID_ADDRESS && m_kernel.GetModule())
1041             {
1042                 // We didn't get a hint from the process, so we will
1043                 // try the kernel at the address that it exists at in
1044                 // the file if we have one
1045                 ObjectFile *kernel_object_file = m_kernel.GetModule()->GetObjectFile();
1046                 if (kernel_object_file)
1047                 {
1048                     addr_t load_address = kernel_object_file->GetHeaderAddress().GetLoadAddress(&m_process->GetTarget());
1049                     addr_t file_address = kernel_object_file->GetHeaderAddress().GetFileAddress();
1050                     if (load_address != LLDB_INVALID_ADDRESS && load_address != 0)
1051                     {
1052                         m_kernel.SetLoadAddress (load_address);
1053                         if (load_address != file_address)
1054                         {
1055                             // Don't accidentally relocate the kernel to the File address --
1056                             // the Load address has already been set to its actual in-memory address.
1057                             // Mark it as IsLoaded.
1058                             m_kernel.SetProcessStopId (m_process->GetStopID());
1059                         }
1060                     }
1061                     else
1062                     {
1063                         m_kernel.SetLoadAddress(file_address);
1064                     }
1065                 }
1066             }
1067         }
1068 
1069         if (m_kernel.GetLoadAddress() != LLDB_INVALID_ADDRESS)
1070         {
1071             if (!m_kernel.LoadImageUsingMemoryModule (m_process))
1072             {
1073                 m_kernel.LoadImageAtFileAddress (m_process);
1074             }
1075         }
1076 
1077         if (m_kernel.IsLoaded() && m_kernel.GetModule())
1078         {
1079             static ConstString kext_summary_symbol ("gLoadedKextSummaries");
1080             const Symbol *symbol = m_kernel.GetModule()->FindFirstSymbolWithNameAndType (kext_summary_symbol, eSymbolTypeData);
1081             if (symbol)
1082             {
1083                 m_kext_summary_header_ptr_addr = symbol->GetAddress();
1084                 // Update all image infos
1085                 ReadAllKextSummaries ();
1086             }
1087         }
1088         else
1089         {
1090             m_kernel.Clear();
1091         }
1092     }
1093 }
1094 
1095 //----------------------------------------------------------------------
1096 // Static callback function that gets called when our DYLD notification
1097 // breakpoint gets hit. We update all of our image infos and then
1098 // let our super class DynamicLoader class decide if we should stop
1099 // or not (based on global preference).
1100 //----------------------------------------------------------------------
1101 bool
1102 DynamicLoaderDarwinKernel::BreakpointHitCallback (void *baton,
1103                                                   StoppointCallbackContext *context,
1104                                                   user_id_t break_id,
1105                                                   user_id_t break_loc_id)
1106 {
1107     return static_cast<DynamicLoaderDarwinKernel*>(baton)->BreakpointHit (context, break_id, break_loc_id);
1108 }
1109 
1110 bool
1111 DynamicLoaderDarwinKernel::BreakpointHit (StoppointCallbackContext *context,
1112                                           user_id_t break_id,
1113                                           user_id_t break_loc_id)
1114 {
1115     Log *log(GetLogIfAnyCategoriesSet (LIBLLDB_LOG_DYNAMIC_LOADER));
1116     if (log)
1117         log->Printf ("DynamicLoaderDarwinKernel::BreakpointHit (...)\n");
1118 
1119     ReadAllKextSummaries ();
1120 
1121     if (log)
1122         PutToLog(log);
1123 
1124     return GetStopWhenImagesChange();
1125 }
1126 
1127 
1128 bool
1129 DynamicLoaderDarwinKernel::ReadKextSummaryHeader ()
1130 {
1131     Mutex::Locker locker(m_mutex);
1132 
1133     // the all image infos is already valid for this process stop ID
1134 
1135     if (m_kext_summary_header_ptr_addr.IsValid())
1136     {
1137         const uint32_t addr_size = m_kernel.GetAddressByteSize ();
1138         const ByteOrder byte_order = m_kernel.GetByteOrder();
1139         Error error;
1140         // Read enough bytes for a "OSKextLoadedKextSummaryHeader" structure
1141         // which is currently 4 uint32_t and a pointer.
1142         uint8_t buf[24];
1143         DataExtractor data (buf, sizeof(buf), byte_order, addr_size);
1144         const size_t count = 4 * sizeof(uint32_t) + addr_size;
1145         const bool prefer_file_cache = false;
1146         if (m_process->GetTarget().ReadPointerFromMemory (m_kext_summary_header_ptr_addr,
1147                                                           prefer_file_cache,
1148                                                           error,
1149                                                           m_kext_summary_header_addr))
1150         {
1151             // We got a valid address for our kext summary header and make sure it isn't NULL
1152             if (m_kext_summary_header_addr.IsValid() &&
1153                 m_kext_summary_header_addr.GetFileAddress() != 0)
1154             {
1155                 const size_t bytes_read = m_process->GetTarget().ReadMemory (m_kext_summary_header_addr, prefer_file_cache, buf, count, error);
1156                 if (bytes_read == count)
1157                 {
1158                     lldb::offset_t offset = 0;
1159                     m_kext_summary_header.version = data.GetU32(&offset);
1160                     if (m_kext_summary_header.version > 128)
1161                     {
1162                         Stream *s = m_process->GetTarget().GetDebugger().GetOutputFile().get();
1163                         s->Printf ("WARNING: Unable to read kext summary header, got improbable version number %u\n", m_kext_summary_header.version);
1164                         // If we get an improbably large version number, we're probably getting bad memory.
1165                         m_kext_summary_header_addr.Clear();
1166                         return false;
1167                     }
1168                     if (m_kext_summary_header.version >= 2)
1169                     {
1170                         m_kext_summary_header.entry_size = data.GetU32(&offset);
1171                         if (m_kext_summary_header.entry_size > 4096)
1172                         {
1173                             // If we get an improbably large entry_size, we're probably getting bad memory.
1174                             Stream *s = m_process->GetTarget().GetDebugger().GetOutputFile().get();
1175                             s->Printf ("WARNING: Unable to read kext summary header, got improbable entry_size %u\n", m_kext_summary_header.entry_size);
1176                             m_kext_summary_header_addr.Clear();
1177                             return false;
1178                         }
1179                     }
1180                     else
1181                     {
1182                         // Versions less than 2 didn't have an entry size, it was hard coded
1183                         m_kext_summary_header.entry_size = KERNEL_MODULE_ENTRY_SIZE_VERSION_1;
1184                     }
1185                     m_kext_summary_header.entry_count = data.GetU32(&offset);
1186                     if (m_kext_summary_header.entry_count > 10000)
1187                     {
1188                         // If we get an improbably large number of kexts, we're probably getting bad memory.
1189                         Stream *s = m_process->GetTarget().GetDebugger().GetOutputFile().get();
1190                         s->Printf ("WARNING: Unable to read kext summary header, got improbable number of kexts %u\n", m_kext_summary_header.entry_count);
1191                         m_kext_summary_header_addr.Clear();
1192                         return false;
1193                     }
1194                     return true;
1195                 }
1196             }
1197         }
1198     }
1199     m_kext_summary_header_addr.Clear();
1200     return false;
1201 }
1202 
1203 // We've either (a) just attached to a new kernel, or (b) the kexts-changed breakpoint was hit
1204 // and we need to figure out what kexts have been added or removed.
1205 // Read the kext summaries from the inferior kernel memory, compare them against the
1206 // m_known_kexts vector and update the m_known_kexts vector as needed to keep in sync with the
1207 // inferior.
1208 
1209 bool
1210 DynamicLoaderDarwinKernel::ParseKextSummaries (const Address &kext_summary_addr, uint32_t count)
1211 {
1212     KextImageInfo::collection kext_summaries;
1213     Log *log(GetLogIfAnyCategoriesSet (LIBLLDB_LOG_DYNAMIC_LOADER));
1214     if (log)
1215         log->Printf ("Kexts-changed breakpoint hit, there are %d kexts currently.\n", count);
1216 
1217     Mutex::Locker locker(m_mutex);
1218 
1219     if (!ReadKextSummaries (kext_summary_addr, count, kext_summaries))
1220         return false;
1221 
1222     // read the plugin.dynamic-loader.darwin-kernel.load-kexts setting -- if the user requested no
1223     // kext loading, don't print any messages about kexts & don't try to read them.
1224     const bool load_kexts = GetGlobalProperties()->GetLoadKexts();
1225 
1226     // By default, all kexts we've loaded in the past are marked as "remove" and all of the kexts
1227     // we just found out about from ReadKextSummaries are marked as "add".
1228     std::vector<bool> to_be_removed(m_known_kexts.size(), true);
1229     std::vector<bool> to_be_added(count, true);
1230 
1231     int number_of_new_kexts_being_added = 0;
1232     int number_of_old_kexts_being_removed = m_known_kexts.size();
1233 
1234     const uint32_t new_kexts_size = kext_summaries.size();
1235     const uint32_t old_kexts_size = m_known_kexts.size();
1236 
1237     // The m_known_kexts vector may have entries that have been Cleared,
1238     // or are a kernel.
1239     for (uint32_t old_kext = 0; old_kext < old_kexts_size; old_kext++)
1240     {
1241         bool ignore = false;
1242         KextImageInfo &image_info = m_known_kexts[old_kext];
1243         if (image_info.IsKernel())
1244         {
1245             ignore = true;
1246         }
1247         else if (image_info.GetLoadAddress() == LLDB_INVALID_ADDRESS && !image_info.GetModule())
1248         {
1249             ignore = true;
1250         }
1251 
1252         if (ignore)
1253         {
1254             number_of_old_kexts_being_removed--;
1255             to_be_removed[old_kext] = false;
1256         }
1257     }
1258 
1259     // Scan over the list of kexts we just read from the kernel, note those that
1260     // need to be added and those already loaded.
1261     for (uint32_t new_kext = 0; new_kext < new_kexts_size; new_kext++)
1262     {
1263         bool add_this_one = true;
1264         for (uint32_t old_kext = 0; old_kext < old_kexts_size; old_kext++)
1265         {
1266             if (m_known_kexts[old_kext] == kext_summaries[new_kext])
1267             {
1268                 // We already have this kext, don't re-load it.
1269                 to_be_added[new_kext] = false;
1270                 // This kext is still present, do not remove it.
1271                 to_be_removed[old_kext] = false;
1272 
1273                 number_of_old_kexts_being_removed--;
1274                 add_this_one = false;
1275                 break;
1276             }
1277         }
1278         if (add_this_one)
1279         {
1280             number_of_new_kexts_being_added++;
1281         }
1282     }
1283 
1284     if (number_of_new_kexts_being_added == 0 && number_of_old_kexts_being_removed == 0)
1285         return true;
1286 
1287     Stream *s = m_process->GetTarget().GetDebugger().GetOutputFile().get();
1288     if (s && load_kexts)
1289     {
1290         if (number_of_new_kexts_being_added > 0 && number_of_old_kexts_being_removed > 0)
1291         {
1292             s->Printf ("Loading %d kext modules and unloading %d kext modules ", number_of_new_kexts_being_added, number_of_old_kexts_being_removed);
1293         }
1294         else if (number_of_new_kexts_being_added > 0)
1295         {
1296             s->Printf ("Loading %d kext modules ", number_of_new_kexts_being_added);
1297         }
1298         else if (number_of_old_kexts_being_removed > 0)
1299         {
1300             s->Printf ("Unloading %d kext modules ", number_of_old_kexts_being_removed);
1301         }
1302     }
1303 
1304     if (log)
1305     {
1306         if (load_kexts)
1307         {
1308             log->Printf ("DynamicLoaderDarwinKernel::ParseKextSummaries: %d kexts added, %d kexts removed", number_of_new_kexts_being_added, number_of_old_kexts_being_removed);
1309         }
1310         else
1311         {
1312             log->Printf ("DynamicLoaderDarwinKernel::ParseKextSummaries kext loading is disabled, else would have %d kexts added, %d kexts removed", number_of_new_kexts_being_added, number_of_old_kexts_being_removed);
1313         }
1314     }
1315 
1316 
1317     if (number_of_new_kexts_being_added > 0)
1318     {
1319         ModuleList loaded_module_list;
1320 
1321         const uint32_t num_of_new_kexts = kext_summaries.size();
1322         for (uint32_t new_kext = 0; new_kext < num_of_new_kexts; new_kext++)
1323         {
1324             if (to_be_added[new_kext] == true)
1325             {
1326                 KextImageInfo &image_info = kext_summaries[new_kext];
1327                 if (load_kexts)
1328                 {
1329                     if (!image_info.LoadImageUsingMemoryModule (m_process))
1330                     {
1331                         image_info.LoadImageAtFileAddress (m_process);
1332                     }
1333                 }
1334 
1335                 m_known_kexts.push_back(image_info);
1336 
1337                 if (image_info.GetModule() && m_process->GetStopID() == image_info.GetProcessStopId())
1338                     loaded_module_list.AppendIfNeeded (image_info.GetModule());
1339 
1340                 if (s && load_kexts)
1341                     s->Printf (".");
1342 
1343                 if (log)
1344                     kext_summaries[new_kext].PutToLog (log);
1345             }
1346         }
1347         m_process->GetTarget().ModulesDidLoad (loaded_module_list);
1348     }
1349 
1350     if (number_of_old_kexts_being_removed > 0)
1351     {
1352         ModuleList loaded_module_list;
1353         const uint32_t num_of_old_kexts = m_known_kexts.size();
1354         for (uint32_t old_kext = 0; old_kext < num_of_old_kexts; old_kext++)
1355         {
1356             ModuleList unloaded_module_list;
1357             if (to_be_removed[old_kext])
1358             {
1359                 KextImageInfo &image_info = m_known_kexts[old_kext];
1360                 // You can't unload the kernel.
1361                 if (!image_info.IsKernel())
1362                 {
1363                     if (image_info.GetModule())
1364                     {
1365                         unloaded_module_list.AppendIfNeeded (image_info.GetModule());
1366                     }
1367                     if (s)
1368                         s->Printf (".");
1369                     image_info.Clear();
1370                     // should pull it out of the KextImageInfos vector but that would mutate the list and invalidate
1371                     // the to_be_removed bool vector; leaving it in place once Cleared() is relatively harmless.
1372                 }
1373             }
1374             m_process->GetTarget().ModulesDidUnload (unloaded_module_list, false);
1375         }
1376     }
1377 
1378     if (s && load_kexts)
1379     {
1380         s->Printf (" done.\n");
1381         s->Flush ();
1382     }
1383 
1384     return true;
1385 }
1386 
1387 uint32_t
1388 DynamicLoaderDarwinKernel::ReadKextSummaries (const Address &kext_summary_addr,
1389                                               uint32_t image_infos_count,
1390                                               KextImageInfo::collection &image_infos)
1391 {
1392     const ByteOrder endian = m_kernel.GetByteOrder();
1393     const uint32_t addr_size = m_kernel.GetAddressByteSize();
1394 
1395     image_infos.resize(image_infos_count);
1396     const size_t count = image_infos.size() * m_kext_summary_header.entry_size;
1397     DataBufferHeap data(count, 0);
1398     Error error;
1399 
1400     const bool prefer_file_cache = false;
1401     const size_t bytes_read = m_process->GetTarget().ReadMemory (kext_summary_addr,
1402                                                                  prefer_file_cache,
1403                                                                  data.GetBytes(),
1404                                                                  data.GetByteSize(),
1405                                                                  error);
1406     if (bytes_read == count)
1407     {
1408 
1409         DataExtractor extractor (data.GetBytes(), data.GetByteSize(), endian, addr_size);
1410         uint32_t i=0;
1411         for (uint32_t kext_summary_offset = 0;
1412              i < image_infos.size() && extractor.ValidOffsetForDataOfSize(kext_summary_offset, m_kext_summary_header.entry_size);
1413              ++i, kext_summary_offset += m_kext_summary_header.entry_size)
1414         {
1415             lldb::offset_t offset = kext_summary_offset;
1416             const void *name_data = extractor.GetData(&offset, KERNEL_MODULE_MAX_NAME);
1417             if (name_data == NULL)
1418                 break;
1419             image_infos[i].SetName ((const char *) name_data);
1420             UUID uuid (extractor.GetData (&offset, 16), 16);
1421             image_infos[i].SetUUID (uuid);
1422             image_infos[i].SetLoadAddress (extractor.GetU64(&offset));
1423             image_infos[i].SetSize (extractor.GetU64(&offset));
1424         }
1425         if (i < image_infos.size())
1426             image_infos.resize(i);
1427     }
1428     else
1429     {
1430         image_infos.clear();
1431     }
1432     return image_infos.size();
1433 }
1434 
1435 bool
1436 DynamicLoaderDarwinKernel::ReadAllKextSummaries ()
1437 {
1438     Mutex::Locker locker(m_mutex);
1439 
1440     if (ReadKextSummaryHeader ())
1441     {
1442         if (m_kext_summary_header.entry_count > 0 && m_kext_summary_header_addr.IsValid())
1443         {
1444             Address summary_addr (m_kext_summary_header_addr);
1445             summary_addr.Slide(m_kext_summary_header.GetSize());
1446             if (!ParseKextSummaries (summary_addr, m_kext_summary_header.entry_count))
1447             {
1448                 m_known_kexts.clear();
1449             }
1450             return true;
1451         }
1452     }
1453     return false;
1454 }
1455 
1456 //----------------------------------------------------------------------
1457 // Dump an image info structure to the file handle provided.
1458 //----------------------------------------------------------------------
1459 void
1460 DynamicLoaderDarwinKernel::KextImageInfo::PutToLog (Log *log) const
1461 {
1462     if (log == NULL)
1463         return;
1464     const uint8_t *u = (uint8_t *) m_uuid.GetBytes();
1465 
1466     if (m_load_address == LLDB_INVALID_ADDRESS)
1467     {
1468         if (u)
1469         {
1470             log->Printf("\tuuid=%2.2X%2.2X%2.2X%2.2X-%2.2X%2.2X-%2.2X%2.2X-%2.2X%2.2X-%2.2X%2.2X%2.2X%2.2X%2.2X%2.2X name=\"%s\" (UNLOADED)",
1471                         u[ 0], u[ 1], u[ 2], u[ 3],
1472                         u[ 4], u[ 5], u[ 6], u[ 7],
1473                         u[ 8], u[ 9], u[10], u[11],
1474                         u[12], u[13], u[14], u[15],
1475                         m_name.c_str());
1476         }
1477         else
1478             log->Printf("\tname=\"%s\" (UNLOADED)", m_name.c_str());
1479     }
1480     else
1481     {
1482         if (u)
1483         {
1484             log->Printf("\taddr=0x%16.16" PRIx64 " size=0x%16.16" PRIx64 " uuid=%2.2X%2.2X%2.2X%2.2X-%2.2X%2.2X-%2.2X%2.2X-%2.2X%2.2X-%2.2X%2.2X%2.2X%2.2X%2.2X%2.2X name=\"%s\"",
1485                         m_load_address, m_size,
1486                         u[ 0], u[ 1], u[ 2], u[ 3], u[ 4], u[ 5], u[ 6], u[ 7],
1487                         u[ 8], u[ 9], u[10], u[11], u[12], u[13], u[14], u[15],
1488                         m_name.c_str());
1489         }
1490         else
1491         {
1492             log->Printf("\t[0x%16.16" PRIx64 " - 0x%16.16" PRIx64 ") name=\"%s\"",
1493                         m_load_address, m_load_address+m_size, m_name.c_str());
1494         }
1495     }
1496 }
1497 
1498 //----------------------------------------------------------------------
1499 // Dump the _dyld_all_image_infos members and all current image infos
1500 // that we have parsed to the file handle provided.
1501 //----------------------------------------------------------------------
1502 void
1503 DynamicLoaderDarwinKernel::PutToLog(Log *log) const
1504 {
1505     if (log == NULL)
1506         return;
1507 
1508     Mutex::Locker locker(m_mutex);
1509     log->Printf("gLoadedKextSummaries = 0x%16.16" PRIx64 " { version=%u, entry_size=%u, entry_count=%u }",
1510                 m_kext_summary_header_addr.GetFileAddress(),
1511                 m_kext_summary_header.version,
1512                 m_kext_summary_header.entry_size,
1513                 m_kext_summary_header.entry_count);
1514 
1515     size_t i;
1516     const size_t count = m_known_kexts.size();
1517     if (count > 0)
1518     {
1519         log->PutCString("Loaded:");
1520         for (i = 0; i<count; i++)
1521             m_known_kexts[i].PutToLog(log);
1522     }
1523 }
1524 
1525 void
1526 DynamicLoaderDarwinKernel::PrivateInitialize(Process *process)
1527 {
1528     DEBUG_PRINTF("DynamicLoaderDarwinKernel::%s() process state = %s\n", __FUNCTION__, StateAsCString(m_process->GetState()));
1529     Clear(true);
1530     m_process = process;
1531 }
1532 
1533 void
1534 DynamicLoaderDarwinKernel::SetNotificationBreakpointIfNeeded ()
1535 {
1536     if (m_break_id == LLDB_INVALID_BREAK_ID && m_kernel.GetModule())
1537     {
1538         DEBUG_PRINTF("DynamicLoaderDarwinKernel::%s() process state = %s\n", __FUNCTION__, StateAsCString(m_process->GetState()));
1539 
1540 
1541         const bool internal_bp = true;
1542         const bool hardware = false;
1543         const LazyBool skip_prologue = eLazyBoolNo;
1544         FileSpecList module_spec_list;
1545         module_spec_list.Append (m_kernel.GetModule()->GetFileSpec());
1546         Breakpoint *bp = m_process->GetTarget().CreateBreakpoint (&module_spec_list,
1547                                                                   NULL,
1548                                                                   "OSKextLoadedKextSummariesUpdated",
1549                                                                   eFunctionNameTypeFull,
1550                                                                   skip_prologue,
1551                                                                   internal_bp,
1552                                                                   hardware).get();
1553 
1554         bp->SetCallback (DynamicLoaderDarwinKernel::BreakpointHitCallback, this, true);
1555         m_break_id = bp->GetID();
1556     }
1557 }
1558 
1559 //----------------------------------------------------------------------
1560 // Member function that gets called when the process state changes.
1561 //----------------------------------------------------------------------
1562 void
1563 DynamicLoaderDarwinKernel::PrivateProcessStateChanged (Process *process, StateType state)
1564 {
1565     DEBUG_PRINTF("DynamicLoaderDarwinKernel::%s(%s)\n", __FUNCTION__, StateAsCString(state));
1566     switch (state)
1567     {
1568     case eStateConnected:
1569     case eStateAttaching:
1570     case eStateLaunching:
1571     case eStateInvalid:
1572     case eStateUnloaded:
1573     case eStateExited:
1574     case eStateDetached:
1575         Clear(false);
1576         break;
1577 
1578     case eStateStopped:
1579         UpdateIfNeeded();
1580         break;
1581 
1582     case eStateRunning:
1583     case eStateStepping:
1584     case eStateCrashed:
1585     case eStateSuspended:
1586         break;
1587     }
1588 }
1589 
1590 ThreadPlanSP
1591 DynamicLoaderDarwinKernel::GetStepThroughTrampolinePlan (Thread &thread, bool stop_others)
1592 {
1593     ThreadPlanSP thread_plan_sp;
1594     Log *log(GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
1595     if (log)
1596         log->Printf ("Could not find symbol for step through.");
1597     return thread_plan_sp;
1598 }
1599 
1600 Error
1601 DynamicLoaderDarwinKernel::CanLoadImage ()
1602 {
1603     Error error;
1604     error.SetErrorString("always unsafe to load or unload shared libraries in the darwin kernel");
1605     return error;
1606 }
1607 
1608 void
1609 DynamicLoaderDarwinKernel::Initialize()
1610 {
1611     PluginManager::RegisterPlugin (GetPluginNameStatic(),
1612                                    GetPluginDescriptionStatic(),
1613                                    CreateInstance,
1614                                    DebuggerInitialize);
1615 }
1616 
1617 void
1618 DynamicLoaderDarwinKernel::Terminate()
1619 {
1620     PluginManager::UnregisterPlugin (CreateInstance);
1621 }
1622 
1623 void
1624 DynamicLoaderDarwinKernel::DebuggerInitialize (lldb_private::Debugger &debugger)
1625 {
1626     if (!PluginManager::GetSettingForDynamicLoaderPlugin (debugger, DynamicLoaderDarwinKernelProperties::GetSettingName()))
1627     {
1628         const bool is_global_setting = true;
1629         PluginManager::CreateSettingForDynamicLoaderPlugin (debugger,
1630                                                             GetGlobalProperties()->GetValueProperties(),
1631                                                             ConstString ("Properties for the DynamicLoaderDarwinKernel plug-in."),
1632                                                             is_global_setting);
1633     }
1634 }
1635 
1636 lldb_private::ConstString
1637 DynamicLoaderDarwinKernel::GetPluginNameStatic()
1638 {
1639     static ConstString g_name("darwin-kernel");
1640     return g_name;
1641 }
1642 
1643 const char *
1644 DynamicLoaderDarwinKernel::GetPluginDescriptionStatic()
1645 {
1646     return "Dynamic loader plug-in that watches for shared library loads/unloads in the MacOSX kernel.";
1647 }
1648 
1649 
1650 //------------------------------------------------------------------
1651 // PluginInterface protocol
1652 //------------------------------------------------------------------
1653 lldb_private::ConstString
1654 DynamicLoaderDarwinKernel::GetPluginName()
1655 {
1656     return GetPluginNameStatic();
1657 }
1658 
1659 uint32_t
1660 DynamicLoaderDarwinKernel::GetPluginVersion()
1661 {
1662     return 1;
1663 }
1664 
1665 lldb::ByteOrder
1666 DynamicLoaderDarwinKernel::GetByteOrderFromMagic (uint32_t magic)
1667 {
1668     switch (magic)
1669     {
1670         case llvm::MachO::MH_MAGIC:
1671         case llvm::MachO::MH_MAGIC_64:
1672             return lldb::endian::InlHostByteOrder();
1673 
1674         case llvm::MachO::MH_CIGAM:
1675         case llvm::MachO::MH_CIGAM_64:
1676             if (lldb::endian::InlHostByteOrder() == lldb::eByteOrderBig)
1677                 return lldb::eByteOrderLittle;
1678             else
1679                 return lldb::eByteOrderBig;
1680 
1681         default:
1682             break;
1683     }
1684     return lldb::eByteOrderInvalid;
1685 }
1686 
1687