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