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/Utility/SafeMachO.h"
11 
12 #include "lldb/Breakpoint/StoppointCallbackContext.h"
13 #include "lldb/Core/DataBuffer.h"
14 #include "lldb/Core/DataBufferHeap.h"
15 #include "lldb/Core/Debugger.h"
16 #include "lldb/Core/Log.h"
17 #include "lldb/Core/Module.h"
18 #include "lldb/Core/ModuleSpec.h"
19 #include "lldb/Core/PluginManager.h"
20 #include "lldb/Core/Section.h"
21 #include "lldb/Core/State.h"
22 #include "lldb/Core/StreamFile.h"
23 #include "lldb/Host/Symbols.h"
24 #include "lldb/Interpreter/OptionValueProperties.h"
25 #include "lldb/Symbol/ObjectFile.h"
26 #include "lldb/Target/RegisterContext.h"
27 #include "lldb/Target/StackFrame.h"
28 #include "lldb/Target/Target.h"
29 #include "lldb/Target/Thread.h"
30 #include "lldb/Target/ThreadPlanRunToAddress.h"
31 #include "Plugins/Platform/MacOSX/PlatformDarwinKernel.h"
32 
33 #include "DynamicLoaderDarwinKernel.h"
34 
35 //#define ENABLE_DEBUG_PRINTF // COMMENT THIS LINE OUT PRIOR TO CHECKIN
36 #ifdef ENABLE_DEBUG_PRINTF
37 #include <stdio.h>
38 #define DEBUG_PRINTF(fmt, ...) printf(fmt, ## __VA_ARGS__)
39 #else
40 #define DEBUG_PRINTF(fmt, ...)
41 #endif
42 
43 using namespace lldb;
44 using namespace lldb_private;
45 
46 // Progressively greater amounts of scanning we will allow
47 // For some targets very early in startup, we can't do any random reads of memory or we can crash the device
48 // so a setting is needed that can completely disable the KASLR scans.
49 
50 enum KASLRScanType
51 {
52     eKASLRScanNone = 0,         // No reading into the inferior at all
53     eKASLRScanLowgloAddresses,  // Check one word of memory for a possible kernel addr, then see if a kernel is there
54     eKASLRScanNearPC,           // Scan backwards from the current $pc looking for kernel; checking at 96 locations total
55     eKASLRScanExhaustiveScan    // Scan through the entire possible kernel address range looking for a kernel
56 };
57 
58 OptionEnumValueElement
59 g_kaslr_kernel_scan_enum_values[] =
60 {
61     { eKASLRScanNone,            "none",            "Do not read memory looking for a Darwin kernel when attaching." },
62     { eKASLRScanLowgloAddresses, "basic",           "Check for the Darwin kernel's load addr in the lowglo page (boot-args=debug) only." },
63     { eKASLRScanNearPC,          "fast-scan",       "Scan near the pc value on attach to find the Darwin kernel's load address."},
64     { eKASLRScanExhaustiveScan,  "exhaustive-scan", "Scan through the entire potential address range of Darwin kernel (only on 32-bit targets)."},
65     { 0, NULL, NULL }
66 };
67 
68 static PropertyDefinition
69 g_properties[] =
70 {
71     { "load-kexts" , OptionValue::eTypeBoolean, true, true, NULL, NULL, "Automatically loads kext images when attaching to a kernel." },
72     { "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." },
73     {  NULL        , OptionValue::eTypeInvalid, false, 0  , NULL, NULL, NULL  }
74 };
75 
76 enum {
77     ePropertyLoadKexts,
78     ePropertyScanType
79 };
80 
81 class DynamicLoaderDarwinKernelProperties : public Properties
82 {
83 public:
84 
85     static ConstString &
86     GetSettingName ()
87     {
88         static ConstString g_setting_name("darwin-kernel");
89         return g_setting_name;
90     }
91 
92     DynamicLoaderDarwinKernelProperties() :
93         Properties ()
94     {
95         m_collection_sp.reset (new OptionValueProperties(GetSettingName()));
96         m_collection_sp->Initialize(g_properties);
97     }
98 
99     virtual
100     ~DynamicLoaderDarwinKernelProperties()
101     {
102     }
103 
104     bool
105     GetLoadKexts() const
106     {
107         const uint32_t idx = ePropertyLoadKexts;
108         return m_collection_sp->GetPropertyAtIndexAsBoolean (NULL, idx, g_properties[idx].default_uint_value != 0);
109     }
110 
111     KASLRScanType
112     GetScanType() const
113     {
114         const uint32_t idx = ePropertyScanType;
115         return (KASLRScanType) m_collection_sp->GetPropertyAtIndexAsEnumeration (NULL, idx, g_properties[idx].default_uint_value);
116     }
117 
118 
119 };
120 
121 typedef std::shared_ptr<DynamicLoaderDarwinKernelProperties> DynamicLoaderDarwinKernelPropertiesSP;
122 
123 static const DynamicLoaderDarwinKernelPropertiesSP &
124 GetGlobalProperties()
125 {
126     static DynamicLoaderDarwinKernelPropertiesSP g_settings_sp;
127     if (!g_settings_sp)
128         g_settings_sp.reset (new DynamicLoaderDarwinKernelProperties ());
129     return g_settings_sp;
130 }
131 
132 //----------------------------------------------------------------------
133 // Create an instance of this class. This function is filled into
134 // the plugin info class that gets handed out by the plugin factory and
135 // allows the lldb to instantiate an instance of this class.
136 //----------------------------------------------------------------------
137 DynamicLoader *
138 DynamicLoaderDarwinKernel::CreateInstance (Process* process, bool force)
139 {
140     if (!force)
141     {
142         // If the user provided an executable binary and it is not a kernel,
143         // this plugin should not create an instance.
144         Module* exe_module = process->GetTarget().GetExecutableModulePointer();
145         if (exe_module)
146         {
147             ObjectFile *object_file = exe_module->GetObjectFile();
148             if (object_file)
149             {
150                 if (object_file->GetStrata() != ObjectFile::eStrataKernel)
151                 {
152                     return NULL;
153                 }
154             }
155         }
156 
157         // If the target's architecture does not look like an Apple environment,
158         // this plugin should not create an instance.
159         const llvm::Triple &triple_ref = process->GetTarget().GetArchitecture().GetTriple();
160         switch (triple_ref.getOS())
161         {
162             case llvm::Triple::Darwin:
163             case llvm::Triple::MacOSX:
164             case llvm::Triple::IOS:
165             case llvm::Triple::TvOS:
166             case llvm::Triple::WatchOS:
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->SetCanRunCode(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     Log *log = lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_HOST);
674     if (m_memory_module_sp.get() != NULL)
675         return true;
676     if (m_load_address == LLDB_INVALID_ADDRESS)
677         return false;
678 
679     FileSpec file_spec;
680     file_spec.SetFile (m_name.c_str(), false);
681 
682     ModuleSP memory_module_sp = process->ReadModuleFromMemory (file_spec, m_load_address);
683 
684     if (memory_module_sp.get() == NULL)
685         return false;
686 
687     bool is_kernel = false;
688     if (memory_module_sp->GetObjectFile())
689     {
690         if (memory_module_sp->GetObjectFile()->GetType() == ObjectFile::eTypeExecutable
691             && memory_module_sp->GetObjectFile()->GetStrata() == ObjectFile::eStrataKernel)
692         {
693             is_kernel = true;
694         }
695         else if (memory_module_sp->GetObjectFile()->GetType() == ObjectFile::eTypeSharedLibrary)
696         {
697             is_kernel = false;
698         }
699     }
700 
701     // If this is a kext, and the kernel specified what UUID we should find at this
702     // load address, require that the memory module have a matching UUID or something
703     // has gone wrong and we should discard it.
704     if (m_uuid.IsValid())
705     {
706         if (m_uuid != memory_module_sp->GetUUID())
707         {
708             if (log)
709             {
710                 log->Printf ("KextImageInfo::ReadMemoryModule the kernel said to find uuid %s at 0x%" PRIx64 " but instead we found uuid %s, throwing it away", m_uuid.GetAsString().c_str(), m_load_address, memory_module_sp->GetUUID().GetAsString().c_str());
711             }
712             return false;
713         }
714     }
715 
716     // If the in-memory Module has a UUID, let's use that.
717     if (!m_uuid.IsValid() && memory_module_sp->GetUUID().IsValid())
718     {
719         m_uuid = memory_module_sp->GetUUID();
720     }
721 
722     m_memory_module_sp = memory_module_sp;
723     m_kernel_image = is_kernel;
724     if (is_kernel)
725     {
726         if (log)
727         {
728             // This is unusual and probably not intended
729             log->Printf ("KextImageInfo::ReadMemoryModule read the kernel binary out of memory");
730         }
731         if (memory_module_sp->GetArchitecture().IsValid())
732         {
733             process->GetTarget().SetArchitecture(memory_module_sp->GetArchitecture());
734         }
735         if (m_uuid.IsValid())
736         {
737             ModuleSP exe_module_sp = process->GetTarget().GetExecutableModule();
738             if (exe_module_sp.get() && exe_module_sp->GetUUID().IsValid())
739             {
740                 if (m_uuid != exe_module_sp->GetUUID())
741                 {
742                     // The user specified a kernel binary that has a different UUID than
743                     // the kernel actually running in memory.  This never ends well;
744                     // clear the user specified kernel binary from the Target.
745 
746                     m_module_sp.reset();
747 
748                     ModuleList user_specified_kernel_list;
749                     user_specified_kernel_list.Append (exe_module_sp);
750                     process->GetTarget().GetImages().Remove (user_specified_kernel_list);
751                 }
752             }
753         }
754     }
755 
756     return true;
757 }
758 
759 bool
760 DynamicLoaderDarwinKernel::KextImageInfo::IsKernel () const
761 {
762     return m_kernel_image == true;
763 }
764 
765 void
766 DynamicLoaderDarwinKernel::KextImageInfo::SetIsKernel (bool is_kernel)
767 {
768     m_kernel_image = is_kernel;
769 }
770 
771 bool
772 DynamicLoaderDarwinKernel::KextImageInfo::LoadImageUsingMemoryModule (Process *process)
773 {
774     if (IsLoaded())
775         return true;
776 
777 
778     Target &target = process->GetTarget();
779 
780     // If we don't have / can't create a memory module for this kext, don't try to load it - we won't
781     // have the correct segment load addresses.
782     if (!ReadMemoryModule (process))
783     {
784         return false;
785     }
786 
787     bool uuid_is_valid = m_uuid.IsValid();
788 
789     if (IsKernel() && uuid_is_valid && m_memory_module_sp.get())
790     {
791         Stream *s = target.GetDebugger().GetOutputFile().get();
792         if (s)
793         {
794             s->Printf ("Kernel UUID: %s\n", m_memory_module_sp->GetUUID().GetAsString().c_str());
795             s->Printf ("Load Address: 0x%" PRIx64 "\n", m_load_address);
796         }
797     }
798 
799     if (!m_module_sp)
800     {
801         // See if the kext has already been loaded into the target, probably by the user doing target modules add.
802         const ModuleList &target_images = target.GetImages();
803         m_module_sp = target_images.FindModule(m_uuid);
804 
805         // Search for the kext on the local filesystem via the UUID
806         if (!m_module_sp && uuid_is_valid)
807         {
808             ModuleSpec module_spec;
809             module_spec.GetUUID() = m_uuid;
810             module_spec.GetArchitecture() = target.GetArchitecture();
811 
812             // For the kernel, we really do need an on-disk file copy of the binary to do anything useful.
813             // This will force a clal to
814             if (IsKernel())
815             {
816                 if (Symbols::DownloadObjectAndSymbolFile (module_spec, true))
817                 {
818                     if (module_spec.GetFileSpec().Exists())
819                     {
820                         m_module_sp.reset(new Module (module_spec.GetFileSpec(), target.GetArchitecture()));
821                         if (m_module_sp.get() && m_module_sp->MatchesModuleSpec (module_spec))
822                         {
823                             ModuleList loaded_module_list;
824                             loaded_module_list.Append (m_module_sp);
825                             target.ModulesDidLoad (loaded_module_list);
826                         }
827                     }
828                 }
829             }
830 
831             // If the current platform is PlatformDarwinKernel, create a ModuleSpec with the filename set
832             // to be the bundle ID for this kext, e.g. "com.apple.filesystems.msdosfs", and ask the platform
833             // to find it.
834             PlatformSP platform_sp (target.GetPlatform());
835             if (!m_module_sp && platform_sp)
836             {
837                 ConstString platform_name (platform_sp->GetPluginName());
838                 static ConstString g_platform_name (PlatformDarwinKernel::GetPluginNameStatic());
839                 if (platform_name == g_platform_name)
840                 {
841                     ModuleSpec kext_bundle_module_spec(module_spec);
842                     FileSpec kext_filespec(m_name.c_str(), false);
843                     kext_bundle_module_spec.GetFileSpec() = kext_filespec;
844                     platform_sp->GetSharedModule (kext_bundle_module_spec, process, m_module_sp, &target.GetExecutableSearchPaths(), NULL, NULL);
845                 }
846             }
847 
848             // Ask the Target to find this file on the local system, if possible.
849             // This will search in the list of currently-loaded files, look in the
850             // standard search paths on the system, and on a Mac it will try calling
851             // the DebugSymbols framework with the UUID to find the binary via its
852             // search methods.
853             if (!m_module_sp)
854             {
855                 m_module_sp = target.GetSharedModule (module_spec);
856             }
857 
858             if (IsKernel() && !m_module_sp)
859             {
860                 Stream *s = target.GetDebugger().GetOutputFile().get();
861                 if (s)
862                 {
863                     s->Printf ("WARNING: Unable to locate kernel binary on the debugger system.\n");
864                 }
865             }
866         }
867 
868         // If we managed to find a module, append it to the target's list of images.
869         // If we also have a memory module, require that they have matching UUIDs
870         if (m_module_sp)
871         {
872             bool uuid_match_ok = true;
873             if (m_memory_module_sp)
874             {
875                 if (m_module_sp->GetUUID() != m_memory_module_sp->GetUUID())
876                 {
877                     uuid_match_ok = false;
878                 }
879             }
880             if (uuid_match_ok)
881             {
882                 target.GetImages().AppendIfNeeded(m_module_sp);
883                 if (IsKernel() && target.GetExecutableModulePointer() != m_module_sp.get())
884                 {
885                     target.SetExecutableModule (m_module_sp, false);
886                 }
887             }
888         }
889     }
890 
891     if (!m_module_sp && !IsKernel() && m_uuid.IsValid() && !m_name.empty())
892     {
893         Stream *s = target.GetDebugger().GetOutputFile().get();
894         if (s)
895         {
896             s->Printf ("warning: Can't find binary/dSYM for %s (%s)\n",
897                        m_name.c_str(), m_uuid.GetAsString().c_str());
898         }
899     }
900 
901     static ConstString g_section_name_LINKEDIT ("__LINKEDIT");
902 
903     if (m_memory_module_sp && m_module_sp)
904     {
905         if (m_module_sp->GetUUID() == m_memory_module_sp->GetUUID())
906         {
907             ObjectFile *ondisk_object_file = m_module_sp->GetObjectFile();
908             ObjectFile *memory_object_file = m_memory_module_sp->GetObjectFile();
909 
910             if (memory_object_file && ondisk_object_file)
911             {
912                 // The memory_module for kexts may have an invalid __LINKEDIT seg; skip it.
913                 const bool ignore_linkedit = !IsKernel ();
914 
915                 SectionList *ondisk_section_list = ondisk_object_file->GetSectionList ();
916                 SectionList *memory_section_list = memory_object_file->GetSectionList ();
917                 if (memory_section_list && ondisk_section_list)
918                 {
919                     const uint32_t num_ondisk_sections = ondisk_section_list->GetSize();
920                     // There may be CTF sections in the memory image so we can't
921                     // always just compare the number of sections (which are actually
922                     // segments in mach-o parlance)
923                     uint32_t sect_idx = 0;
924 
925                     // Use the memory_module's addresses for each section to set the
926                     // file module's load address as appropriate.  We don't want to use
927                     // a single slide value for the entire kext - different segments may
928                     // be slid different amounts by the kext loader.
929 
930                     uint32_t num_sections_loaded = 0;
931                     for (sect_idx=0; sect_idx<num_ondisk_sections; ++sect_idx)
932                     {
933                         SectionSP ondisk_section_sp(ondisk_section_list->GetSectionAtIndex(sect_idx));
934                         if (ondisk_section_sp)
935                         {
936                             // Don't ever load __LINKEDIT as it may or may not be actually
937                             // mapped into memory and there is no current way to tell.
938                             // I filed rdar://problem/12851706 to track being able to tell
939                             // if the __LINKEDIT is actually mapped, but until then, we need
940                             // to not load the __LINKEDIT
941                             if (ignore_linkedit && ondisk_section_sp->GetName() == g_section_name_LINKEDIT)
942                                 continue;
943 
944                             const Section *memory_section = memory_section_list->FindSectionByName(ondisk_section_sp->GetName()).get();
945                             if (memory_section)
946                             {
947                                 target.SetSectionLoadAddress (ondisk_section_sp, memory_section->GetFileAddress());
948                                 ++num_sections_loaded;
949                             }
950                         }
951                     }
952                     if (num_sections_loaded > 0)
953                         m_load_process_stop_id = process->GetStopID();
954                     else
955                         m_module_sp.reset(); // No sections were loaded
956                 }
957                 else
958                     m_module_sp.reset(); // One or both section lists
959             }
960             else
961                 m_module_sp.reset(); // One or both object files missing
962         }
963         else
964             m_module_sp.reset(); // UUID mismatch
965     }
966 
967     bool is_loaded = IsLoaded();
968 
969     if (is_loaded && m_module_sp && IsKernel())
970     {
971         Stream *s = target.GetDebugger().GetOutputFile().get();
972         if (s)
973         {
974             ObjectFile *kernel_object_file = m_module_sp->GetObjectFile();
975             if (kernel_object_file)
976             {
977                 addr_t file_address = kernel_object_file->GetHeaderAddress().GetFileAddress();
978                 if (m_load_address != LLDB_INVALID_ADDRESS && file_address != LLDB_INVALID_ADDRESS)
979                 {
980                     s->Printf ("Kernel slid 0x%" PRIx64 " in memory.\n", m_load_address - file_address);
981                 }
982             }
983             {
984                 s->Printf ("Loaded kernel file %s\n",
985                            m_module_sp->GetFileSpec().GetPath().c_str());
986             }
987             s->Flush ();
988         }
989     }
990     return is_loaded;
991 }
992 
993 uint32_t
994 DynamicLoaderDarwinKernel::KextImageInfo::GetAddressByteSize ()
995 {
996     if (m_memory_module_sp)
997         return m_memory_module_sp->GetArchitecture().GetAddressByteSize();
998     if (m_module_sp)
999         return m_module_sp->GetArchitecture().GetAddressByteSize();
1000     return 0;
1001 }
1002 
1003 lldb::ByteOrder
1004 DynamicLoaderDarwinKernel::KextImageInfo::GetByteOrder()
1005 {
1006     if (m_memory_module_sp)
1007         return m_memory_module_sp->GetArchitecture().GetByteOrder();
1008     if (m_module_sp)
1009         return m_module_sp->GetArchitecture().GetByteOrder();
1010     return endian::InlHostByteOrder();
1011 }
1012 
1013 lldb_private::ArchSpec
1014 DynamicLoaderDarwinKernel::KextImageInfo::GetArchitecture () const
1015 {
1016     if (m_memory_module_sp)
1017         return m_memory_module_sp->GetArchitecture();
1018     if (m_module_sp)
1019         return m_module_sp->GetArchitecture();
1020     return lldb_private::ArchSpec ();
1021 }
1022 
1023 
1024 //----------------------------------------------------------------------
1025 // Load the kernel module and initialize the "m_kernel" member. Return
1026 // true _only_ if the kernel is loaded the first time through (subsequent
1027 // calls to this function should return false after the kernel has been
1028 // already loaded).
1029 //----------------------------------------------------------------------
1030 void
1031 DynamicLoaderDarwinKernel::LoadKernelModuleIfNeeded()
1032 {
1033     if (!m_kext_summary_header_ptr_addr.IsValid())
1034     {
1035         m_kernel.Clear();
1036         m_kernel.SetModule (m_process->GetTarget().GetExecutableModule());
1037         m_kernel.SetIsKernel(true);
1038 
1039         ConstString kernel_name("mach_kernel");
1040         if (m_kernel.GetModule().get()
1041             && m_kernel.GetModule()->GetObjectFile()
1042             && !m_kernel.GetModule()->GetObjectFile()->GetFileSpec().GetFilename().IsEmpty())
1043         {
1044             kernel_name = m_kernel.GetModule()->GetObjectFile()->GetFileSpec().GetFilename();
1045         }
1046         m_kernel.SetName (kernel_name.AsCString());
1047 
1048         if (m_kernel.GetLoadAddress() == LLDB_INVALID_ADDRESS)
1049         {
1050             m_kernel.SetLoadAddress(m_kernel_load_address);
1051             if (m_kernel.GetLoadAddress() == LLDB_INVALID_ADDRESS && m_kernel.GetModule())
1052             {
1053                 // We didn't get a hint from the process, so we will
1054                 // try the kernel at the address that it exists at in
1055                 // the file if we have one
1056                 ObjectFile *kernel_object_file = m_kernel.GetModule()->GetObjectFile();
1057                 if (kernel_object_file)
1058                 {
1059                     addr_t load_address = kernel_object_file->GetHeaderAddress().GetLoadAddress(&m_process->GetTarget());
1060                     addr_t file_address = kernel_object_file->GetHeaderAddress().GetFileAddress();
1061                     if (load_address != LLDB_INVALID_ADDRESS && load_address != 0)
1062                     {
1063                         m_kernel.SetLoadAddress (load_address);
1064                         if (load_address != file_address)
1065                         {
1066                             // Don't accidentally relocate the kernel to the File address --
1067                             // the Load address has already been set to its actual in-memory address.
1068                             // Mark it as IsLoaded.
1069                             m_kernel.SetProcessStopId (m_process->GetStopID());
1070                         }
1071                     }
1072                     else
1073                     {
1074                         m_kernel.SetLoadAddress(file_address);
1075                     }
1076                 }
1077             }
1078         }
1079 
1080         if (m_kernel.GetLoadAddress() != LLDB_INVALID_ADDRESS)
1081         {
1082             if (!m_kernel.LoadImageUsingMemoryModule (m_process))
1083             {
1084                 m_kernel.LoadImageAtFileAddress (m_process);
1085             }
1086         }
1087 
1088         if (m_kernel.IsLoaded() && m_kernel.GetModule())
1089         {
1090             static ConstString kext_summary_symbol ("gLoadedKextSummaries");
1091             const Symbol *symbol = m_kernel.GetModule()->FindFirstSymbolWithNameAndType (kext_summary_symbol, eSymbolTypeData);
1092             if (symbol)
1093             {
1094                 m_kext_summary_header_ptr_addr = symbol->GetAddress();
1095                 // Update all image infos
1096                 ReadAllKextSummaries ();
1097             }
1098         }
1099         else
1100         {
1101             m_kernel.Clear();
1102         }
1103     }
1104 }
1105 
1106 //----------------------------------------------------------------------
1107 // Static callback function that gets called when our DYLD notification
1108 // breakpoint gets hit. We update all of our image infos and then
1109 // let our super class DynamicLoader class decide if we should stop
1110 // or not (based on global preference).
1111 //----------------------------------------------------------------------
1112 bool
1113 DynamicLoaderDarwinKernel::BreakpointHitCallback (void *baton,
1114                                                   StoppointCallbackContext *context,
1115                                                   user_id_t break_id,
1116                                                   user_id_t break_loc_id)
1117 {
1118     return static_cast<DynamicLoaderDarwinKernel*>(baton)->BreakpointHit (context, break_id, break_loc_id);
1119 }
1120 
1121 bool
1122 DynamicLoaderDarwinKernel::BreakpointHit (StoppointCallbackContext *context,
1123                                           user_id_t break_id,
1124                                           user_id_t break_loc_id)
1125 {
1126     Log *log(GetLogIfAnyCategoriesSet (LIBLLDB_LOG_DYNAMIC_LOADER));
1127     if (log)
1128         log->Printf ("DynamicLoaderDarwinKernel::BreakpointHit (...)\n");
1129 
1130     ReadAllKextSummaries ();
1131 
1132     if (log)
1133         PutToLog(log);
1134 
1135     return GetStopWhenImagesChange();
1136 }
1137 
1138 
1139 bool
1140 DynamicLoaderDarwinKernel::ReadKextSummaryHeader ()
1141 {
1142     Mutex::Locker locker(m_mutex);
1143 
1144     // the all image infos is already valid for this process stop ID
1145 
1146     if (m_kext_summary_header_ptr_addr.IsValid())
1147     {
1148         const uint32_t addr_size = m_kernel.GetAddressByteSize ();
1149         const ByteOrder byte_order = m_kernel.GetByteOrder();
1150         Error error;
1151         // Read enough bytes for a "OSKextLoadedKextSummaryHeader" structure
1152         // which is currently 4 uint32_t and a pointer.
1153         uint8_t buf[24];
1154         DataExtractor data (buf, sizeof(buf), byte_order, addr_size);
1155         const size_t count = 4 * sizeof(uint32_t) + addr_size;
1156         const bool prefer_file_cache = false;
1157         if (m_process->GetTarget().ReadPointerFromMemory (m_kext_summary_header_ptr_addr,
1158                                                           prefer_file_cache,
1159                                                           error,
1160                                                           m_kext_summary_header_addr))
1161         {
1162             // We got a valid address for our kext summary header and make sure it isn't NULL
1163             if (m_kext_summary_header_addr.IsValid() &&
1164                 m_kext_summary_header_addr.GetFileAddress() != 0)
1165             {
1166                 const size_t bytes_read = m_process->GetTarget().ReadMemory (m_kext_summary_header_addr, prefer_file_cache, buf, count, error);
1167                 if (bytes_read == count)
1168                 {
1169                     lldb::offset_t offset = 0;
1170                     m_kext_summary_header.version = data.GetU32(&offset);
1171                     if (m_kext_summary_header.version > 128)
1172                     {
1173                         Stream *s = m_process->GetTarget().GetDebugger().GetOutputFile().get();
1174                         s->Printf ("WARNING: Unable to read kext summary header, got improbable version number %u\n", m_kext_summary_header.version);
1175                         // If we get an improbably large version number, we're probably getting bad memory.
1176                         m_kext_summary_header_addr.Clear();
1177                         return false;
1178                     }
1179                     if (m_kext_summary_header.version >= 2)
1180                     {
1181                         m_kext_summary_header.entry_size = data.GetU32(&offset);
1182                         if (m_kext_summary_header.entry_size > 4096)
1183                         {
1184                             // If we get an improbably large entry_size, we're probably getting bad memory.
1185                             Stream *s = m_process->GetTarget().GetDebugger().GetOutputFile().get();
1186                             s->Printf ("WARNING: Unable to read kext summary header, got improbable entry_size %u\n", m_kext_summary_header.entry_size);
1187                             m_kext_summary_header_addr.Clear();
1188                             return false;
1189                         }
1190                     }
1191                     else
1192                     {
1193                         // Versions less than 2 didn't have an entry size, it was hard coded
1194                         m_kext_summary_header.entry_size = KERNEL_MODULE_ENTRY_SIZE_VERSION_1;
1195                     }
1196                     m_kext_summary_header.entry_count = data.GetU32(&offset);
1197                     if (m_kext_summary_header.entry_count > 10000)
1198                     {
1199                         // If we get an improbably large number of kexts, we're probably getting bad memory.
1200                         Stream *s = m_process->GetTarget().GetDebugger().GetOutputFile().get();
1201                         s->Printf ("WARNING: Unable to read kext summary header, got improbable number of kexts %u\n", m_kext_summary_header.entry_count);
1202                         m_kext_summary_header_addr.Clear();
1203                         return false;
1204                     }
1205                     return true;
1206                 }
1207             }
1208         }
1209     }
1210     m_kext_summary_header_addr.Clear();
1211     return false;
1212 }
1213 
1214 // We've either (a) just attached to a new kernel, or (b) the kexts-changed breakpoint was hit
1215 // and we need to figure out what kexts have been added or removed.
1216 // Read the kext summaries from the inferior kernel memory, compare them against the
1217 // m_known_kexts vector and update the m_known_kexts vector as needed to keep in sync with the
1218 // inferior.
1219 
1220 bool
1221 DynamicLoaderDarwinKernel::ParseKextSummaries (const Address &kext_summary_addr, uint32_t count)
1222 {
1223     KextImageInfo::collection kext_summaries;
1224     Log *log(GetLogIfAnyCategoriesSet (LIBLLDB_LOG_DYNAMIC_LOADER));
1225     if (log)
1226         log->Printf ("Kexts-changed breakpoint hit, there are %d kexts currently.\n", count);
1227 
1228     Mutex::Locker locker(m_mutex);
1229 
1230     if (!ReadKextSummaries (kext_summary_addr, count, kext_summaries))
1231         return false;
1232 
1233     // read the plugin.dynamic-loader.darwin-kernel.load-kexts setting -- if the user requested no
1234     // kext loading, don't print any messages about kexts & don't try to read them.
1235     const bool load_kexts = GetGlobalProperties()->GetLoadKexts();
1236 
1237     // By default, all kexts we've loaded in the past are marked as "remove" and all of the kexts
1238     // we just found out about from ReadKextSummaries are marked as "add".
1239     std::vector<bool> to_be_removed(m_known_kexts.size(), true);
1240     std::vector<bool> to_be_added(count, true);
1241 
1242     int number_of_new_kexts_being_added = 0;
1243     int number_of_old_kexts_being_removed = m_known_kexts.size();
1244 
1245     const uint32_t new_kexts_size = kext_summaries.size();
1246     const uint32_t old_kexts_size = m_known_kexts.size();
1247 
1248     // The m_known_kexts vector may have entries that have been Cleared,
1249     // or are a kernel.
1250     for (uint32_t old_kext = 0; old_kext < old_kexts_size; old_kext++)
1251     {
1252         bool ignore = false;
1253         KextImageInfo &image_info = m_known_kexts[old_kext];
1254         if (image_info.IsKernel())
1255         {
1256             ignore = true;
1257         }
1258         else if (image_info.GetLoadAddress() == LLDB_INVALID_ADDRESS && !image_info.GetModule())
1259         {
1260             ignore = true;
1261         }
1262 
1263         if (ignore)
1264         {
1265             number_of_old_kexts_being_removed--;
1266             to_be_removed[old_kext] = false;
1267         }
1268     }
1269 
1270     // Scan over the list of kexts we just read from the kernel, note those that
1271     // need to be added and those already loaded.
1272     for (uint32_t new_kext = 0; new_kext < new_kexts_size; new_kext++)
1273     {
1274         bool add_this_one = true;
1275         for (uint32_t old_kext = 0; old_kext < old_kexts_size; old_kext++)
1276         {
1277             if (m_known_kexts[old_kext] == kext_summaries[new_kext])
1278             {
1279                 // We already have this kext, don't re-load it.
1280                 to_be_added[new_kext] = false;
1281                 // This kext is still present, do not remove it.
1282                 to_be_removed[old_kext] = false;
1283 
1284                 number_of_old_kexts_being_removed--;
1285                 add_this_one = false;
1286                 break;
1287             }
1288         }
1289         if (add_this_one)
1290         {
1291             number_of_new_kexts_being_added++;
1292         }
1293     }
1294 
1295     if (number_of_new_kexts_being_added == 0 && number_of_old_kexts_being_removed == 0)
1296         return true;
1297 
1298     Stream *s = m_process->GetTarget().GetDebugger().GetOutputFile().get();
1299     if (s && load_kexts)
1300     {
1301         if (number_of_new_kexts_being_added > 0 && number_of_old_kexts_being_removed > 0)
1302         {
1303             s->Printf ("Loading %d kext modules and unloading %d kext modules ", number_of_new_kexts_being_added, number_of_old_kexts_being_removed);
1304         }
1305         else if (number_of_new_kexts_being_added > 0)
1306         {
1307             s->Printf ("Loading %d kext modules ", number_of_new_kexts_being_added);
1308         }
1309         else if (number_of_old_kexts_being_removed > 0)
1310         {
1311             s->Printf ("Unloading %d kext modules ", number_of_old_kexts_being_removed);
1312         }
1313     }
1314 
1315     if (log)
1316     {
1317         if (load_kexts)
1318         {
1319             log->Printf ("DynamicLoaderDarwinKernel::ParseKextSummaries: %d kexts added, %d kexts removed", number_of_new_kexts_being_added, number_of_old_kexts_being_removed);
1320         }
1321         else
1322         {
1323             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);
1324         }
1325     }
1326 
1327 
1328     if (number_of_new_kexts_being_added > 0)
1329     {
1330         ModuleList loaded_module_list;
1331 
1332         const uint32_t num_of_new_kexts = kext_summaries.size();
1333         for (uint32_t new_kext = 0; new_kext < num_of_new_kexts; new_kext++)
1334         {
1335             if (to_be_added[new_kext] == true)
1336             {
1337                 KextImageInfo &image_info = kext_summaries[new_kext];
1338                 if (load_kexts)
1339                 {
1340                     if (!image_info.LoadImageUsingMemoryModule (m_process))
1341                     {
1342                         image_info.LoadImageAtFileAddress (m_process);
1343                     }
1344                 }
1345 
1346                 m_known_kexts.push_back(image_info);
1347 
1348                 if (image_info.GetModule() && m_process->GetStopID() == image_info.GetProcessStopId())
1349                     loaded_module_list.AppendIfNeeded (image_info.GetModule());
1350 
1351                 if (s && load_kexts)
1352                     s->Printf (".");
1353 
1354                 if (log)
1355                     kext_summaries[new_kext].PutToLog (log);
1356             }
1357         }
1358         m_process->GetTarget().ModulesDidLoad (loaded_module_list);
1359     }
1360 
1361     if (number_of_old_kexts_being_removed > 0)
1362     {
1363         ModuleList loaded_module_list;
1364         const uint32_t num_of_old_kexts = m_known_kexts.size();
1365         for (uint32_t old_kext = 0; old_kext < num_of_old_kexts; old_kext++)
1366         {
1367             ModuleList unloaded_module_list;
1368             if (to_be_removed[old_kext])
1369             {
1370                 KextImageInfo &image_info = m_known_kexts[old_kext];
1371                 // You can't unload the kernel.
1372                 if (!image_info.IsKernel())
1373                 {
1374                     if (image_info.GetModule())
1375                     {
1376                         unloaded_module_list.AppendIfNeeded (image_info.GetModule());
1377                     }
1378                     if (s)
1379                         s->Printf (".");
1380                     image_info.Clear();
1381                     // should pull it out of the KextImageInfos vector but that would mutate the list and invalidate
1382                     // the to_be_removed bool vector; leaving it in place once Cleared() is relatively harmless.
1383                 }
1384             }
1385             m_process->GetTarget().ModulesDidUnload (unloaded_module_list, false);
1386         }
1387     }
1388 
1389     if (s && load_kexts)
1390     {
1391         s->Printf (" done.\n");
1392         s->Flush ();
1393     }
1394 
1395     return true;
1396 }
1397 
1398 uint32_t
1399 DynamicLoaderDarwinKernel::ReadKextSummaries (const Address &kext_summary_addr,
1400                                               uint32_t image_infos_count,
1401                                               KextImageInfo::collection &image_infos)
1402 {
1403     const ByteOrder endian = m_kernel.GetByteOrder();
1404     const uint32_t addr_size = m_kernel.GetAddressByteSize();
1405 
1406     image_infos.resize(image_infos_count);
1407     const size_t count = image_infos.size() * m_kext_summary_header.entry_size;
1408     DataBufferHeap data(count, 0);
1409     Error error;
1410 
1411     const bool prefer_file_cache = false;
1412     const size_t bytes_read = m_process->GetTarget().ReadMemory (kext_summary_addr,
1413                                                                  prefer_file_cache,
1414                                                                  data.GetBytes(),
1415                                                                  data.GetByteSize(),
1416                                                                  error);
1417     if (bytes_read == count)
1418     {
1419 
1420         DataExtractor extractor (data.GetBytes(), data.GetByteSize(), endian, addr_size);
1421         uint32_t i=0;
1422         for (uint32_t kext_summary_offset = 0;
1423              i < image_infos.size() && extractor.ValidOffsetForDataOfSize(kext_summary_offset, m_kext_summary_header.entry_size);
1424              ++i, kext_summary_offset += m_kext_summary_header.entry_size)
1425         {
1426             lldb::offset_t offset = kext_summary_offset;
1427             const void *name_data = extractor.GetData(&offset, KERNEL_MODULE_MAX_NAME);
1428             if (name_data == NULL)
1429                 break;
1430             image_infos[i].SetName ((const char *) name_data);
1431             UUID uuid (extractor.GetData (&offset, 16), 16);
1432             image_infos[i].SetUUID (uuid);
1433             image_infos[i].SetLoadAddress (extractor.GetU64(&offset));
1434             image_infos[i].SetSize (extractor.GetU64(&offset));
1435         }
1436         if (i < image_infos.size())
1437             image_infos.resize(i);
1438     }
1439     else
1440     {
1441         image_infos.clear();
1442     }
1443     return image_infos.size();
1444 }
1445 
1446 bool
1447 DynamicLoaderDarwinKernel::ReadAllKextSummaries ()
1448 {
1449     Mutex::Locker locker(m_mutex);
1450 
1451     if (ReadKextSummaryHeader ())
1452     {
1453         if (m_kext_summary_header.entry_count > 0 && m_kext_summary_header_addr.IsValid())
1454         {
1455             Address summary_addr (m_kext_summary_header_addr);
1456             summary_addr.Slide(m_kext_summary_header.GetSize());
1457             if (!ParseKextSummaries (summary_addr, m_kext_summary_header.entry_count))
1458             {
1459                 m_known_kexts.clear();
1460             }
1461             return true;
1462         }
1463     }
1464     return false;
1465 }
1466 
1467 //----------------------------------------------------------------------
1468 // Dump an image info structure to the file handle provided.
1469 //----------------------------------------------------------------------
1470 void
1471 DynamicLoaderDarwinKernel::KextImageInfo::PutToLog (Log *log) const
1472 {
1473     if (log == NULL)
1474         return;
1475     const uint8_t *u = (uint8_t *) m_uuid.GetBytes();
1476 
1477     if (m_load_address == LLDB_INVALID_ADDRESS)
1478     {
1479         if (u)
1480         {
1481             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)",
1482                         u[ 0], u[ 1], u[ 2], u[ 3],
1483                         u[ 4], u[ 5], u[ 6], u[ 7],
1484                         u[ 8], u[ 9], u[10], u[11],
1485                         u[12], u[13], u[14], u[15],
1486                         m_name.c_str());
1487         }
1488         else
1489             log->Printf("\tname=\"%s\" (UNLOADED)", m_name.c_str());
1490     }
1491     else
1492     {
1493         if (u)
1494         {
1495             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\"",
1496                         m_load_address, m_size,
1497                         u[ 0], u[ 1], u[ 2], u[ 3], u[ 4], u[ 5], u[ 6], u[ 7],
1498                         u[ 8], u[ 9], u[10], u[11], u[12], u[13], u[14], u[15],
1499                         m_name.c_str());
1500         }
1501         else
1502         {
1503             log->Printf("\t[0x%16.16" PRIx64 " - 0x%16.16" PRIx64 ") name=\"%s\"",
1504                         m_load_address, m_load_address+m_size, m_name.c_str());
1505         }
1506     }
1507 }
1508 
1509 //----------------------------------------------------------------------
1510 // Dump the _dyld_all_image_infos members and all current image infos
1511 // that we have parsed to the file handle provided.
1512 //----------------------------------------------------------------------
1513 void
1514 DynamicLoaderDarwinKernel::PutToLog(Log *log) const
1515 {
1516     if (log == NULL)
1517         return;
1518 
1519     Mutex::Locker locker(m_mutex);
1520     log->Printf("gLoadedKextSummaries = 0x%16.16" PRIx64 " { version=%u, entry_size=%u, entry_count=%u }",
1521                 m_kext_summary_header_addr.GetFileAddress(),
1522                 m_kext_summary_header.version,
1523                 m_kext_summary_header.entry_size,
1524                 m_kext_summary_header.entry_count);
1525 
1526     size_t i;
1527     const size_t count = m_known_kexts.size();
1528     if (count > 0)
1529     {
1530         log->PutCString("Loaded:");
1531         for (i = 0; i<count; i++)
1532             m_known_kexts[i].PutToLog(log);
1533     }
1534 }
1535 
1536 void
1537 DynamicLoaderDarwinKernel::PrivateInitialize(Process *process)
1538 {
1539     DEBUG_PRINTF("DynamicLoaderDarwinKernel::%s() process state = %s\n", __FUNCTION__, StateAsCString(m_process->GetState()));
1540     Clear(true);
1541     m_process = process;
1542 }
1543 
1544 void
1545 DynamicLoaderDarwinKernel::SetNotificationBreakpointIfNeeded ()
1546 {
1547     if (m_break_id == LLDB_INVALID_BREAK_ID && m_kernel.GetModule())
1548     {
1549         DEBUG_PRINTF("DynamicLoaderDarwinKernel::%s() process state = %s\n", __FUNCTION__, StateAsCString(m_process->GetState()));
1550 
1551 
1552         const bool internal_bp = true;
1553         const bool hardware = false;
1554         const LazyBool skip_prologue = eLazyBoolNo;
1555         FileSpecList module_spec_list;
1556         module_spec_list.Append (m_kernel.GetModule()->GetFileSpec());
1557         Breakpoint *bp = m_process->GetTarget().CreateBreakpoint (&module_spec_list,
1558                                                                   NULL,
1559                                                                   "OSKextLoadedKextSummariesUpdated",
1560                                                                   eFunctionNameTypeFull,
1561                                                                   eLanguageTypeUnknown,
1562                                                                   skip_prologue,
1563                                                                   internal_bp,
1564                                                                   hardware).get();
1565 
1566         bp->SetCallback (DynamicLoaderDarwinKernel::BreakpointHitCallback, this, true);
1567         m_break_id = bp->GetID();
1568     }
1569 }
1570 
1571 //----------------------------------------------------------------------
1572 // Member function that gets called when the process state changes.
1573 //----------------------------------------------------------------------
1574 void
1575 DynamicLoaderDarwinKernel::PrivateProcessStateChanged (Process *process, StateType state)
1576 {
1577     DEBUG_PRINTF("DynamicLoaderDarwinKernel::%s(%s)\n", __FUNCTION__, StateAsCString(state));
1578     switch (state)
1579     {
1580     case eStateConnected:
1581     case eStateAttaching:
1582     case eStateLaunching:
1583     case eStateInvalid:
1584     case eStateUnloaded:
1585     case eStateExited:
1586     case eStateDetached:
1587         Clear(false);
1588         break;
1589 
1590     case eStateStopped:
1591         UpdateIfNeeded();
1592         break;
1593 
1594     case eStateRunning:
1595     case eStateStepping:
1596     case eStateCrashed:
1597     case eStateSuspended:
1598         break;
1599     }
1600 }
1601 
1602 ThreadPlanSP
1603 DynamicLoaderDarwinKernel::GetStepThroughTrampolinePlan (Thread &thread, bool stop_others)
1604 {
1605     ThreadPlanSP thread_plan_sp;
1606     Log *log(GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
1607     if (log)
1608         log->Printf ("Could not find symbol for step through.");
1609     return thread_plan_sp;
1610 }
1611 
1612 Error
1613 DynamicLoaderDarwinKernel::CanLoadImage ()
1614 {
1615     Error error;
1616     error.SetErrorString("always unsafe to load or unload shared libraries in the darwin kernel");
1617     return error;
1618 }
1619 
1620 void
1621 DynamicLoaderDarwinKernel::Initialize()
1622 {
1623     PluginManager::RegisterPlugin (GetPluginNameStatic(),
1624                                    GetPluginDescriptionStatic(),
1625                                    CreateInstance,
1626                                    DebuggerInitialize);
1627 }
1628 
1629 void
1630 DynamicLoaderDarwinKernel::Terminate()
1631 {
1632     PluginManager::UnregisterPlugin (CreateInstance);
1633 }
1634 
1635 void
1636 DynamicLoaderDarwinKernel::DebuggerInitialize (lldb_private::Debugger &debugger)
1637 {
1638     if (!PluginManager::GetSettingForDynamicLoaderPlugin (debugger, DynamicLoaderDarwinKernelProperties::GetSettingName()))
1639     {
1640         const bool is_global_setting = true;
1641         PluginManager::CreateSettingForDynamicLoaderPlugin (debugger,
1642                                                             GetGlobalProperties()->GetValueProperties(),
1643                                                             ConstString ("Properties for the DynamicLoaderDarwinKernel plug-in."),
1644                                                             is_global_setting);
1645     }
1646 }
1647 
1648 lldb_private::ConstString
1649 DynamicLoaderDarwinKernel::GetPluginNameStatic()
1650 {
1651     static ConstString g_name("darwin-kernel");
1652     return g_name;
1653 }
1654 
1655 const char *
1656 DynamicLoaderDarwinKernel::GetPluginDescriptionStatic()
1657 {
1658     return "Dynamic loader plug-in that watches for shared library loads/unloads in the MacOSX kernel.";
1659 }
1660 
1661 
1662 //------------------------------------------------------------------
1663 // PluginInterface protocol
1664 //------------------------------------------------------------------
1665 lldb_private::ConstString
1666 DynamicLoaderDarwinKernel::GetPluginName()
1667 {
1668     return GetPluginNameStatic();
1669 }
1670 
1671 uint32_t
1672 DynamicLoaderDarwinKernel::GetPluginVersion()
1673 {
1674     return 1;
1675 }
1676 
1677 lldb::ByteOrder
1678 DynamicLoaderDarwinKernel::GetByteOrderFromMagic (uint32_t magic)
1679 {
1680     switch (magic)
1681     {
1682         case llvm::MachO::MH_MAGIC:
1683         case llvm::MachO::MH_MAGIC_64:
1684             return endian::InlHostByteOrder();
1685 
1686         case llvm::MachO::MH_CIGAM:
1687         case llvm::MachO::MH_CIGAM_64:
1688             if (endian::InlHostByteOrder() == lldb::eByteOrderBig)
1689                 return lldb::eByteOrderLittle;
1690             else
1691                 return lldb::eByteOrderBig;
1692 
1693         default:
1694             break;
1695     }
1696     return lldb::eByteOrderInvalid;
1697 }
1698 
1699