DBGPlugInDarwin.cpp@ 53369

Last change on this file since 53369 was 52838, checked in by vboxsync, 10 years ago
dbgDiggerDarwinInit: Fixed wrong sizeof kmod_info_t for 32-bit kernels.
Property svn:eol-style set to `native` Property svn:keywords set to `Author Date Id Revision`
File size: 28.7 KB

Line
1	/* $Id: DBGPlugInDarwin.cpp 52838 2014-09-24 13:09:57Z vboxsync $ */
2	/** @file
3	* DBGPlugInDarwin - Debugger and Guest OS Digger Plugin For Darwin / OS X.
4	*/
5
6	/*
7	* Copyright (C) 2008-2013 Oracle Corporation
8	*
9	* This file is part of VirtualBox Open Source Edition (OSE), as
10	* available from http://www.virtualbox.org. This file is free software;
11	* you can redistribute it and/or modify it under the terms of the GNU
12	* General Public License (GPL) as published by the Free Software
13	* Foundation, in version 2 as it comes in the "COPYING" file of the
14	* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
15	* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
16	*/
17
18
19	/*******************************************************************************
20	* Header Files *
21	*******************************************************************************/
22	#define LOG_GROUP LOG_GROUP_DBGF ///@todo add new log group.
23	#include "DBGPlugIns.h"
24	#include <VBox/vmm/dbgf.h>
25	#include <iprt/string.h>
26	#include <iprt/mem.h>
27	#include <iprt/stream.h>
28	#include <iprt/uuid.h>
29	#include <iprt/ctype.h>
30	#include <iprt/formats/mach-o.h>
31
32
33	/*******************************************************************************
34	* Structures and Typedefs *
35	*******************************************************************************/
36
37	/** @name Internal Darwin structures
38	* @{ */
39
40	/**
41	* 32-bit darwin kernel module info structure (kmod_info_t).
42	*/
43	typedef struct OSX32_kmod_info
44	{
45	uint32_t next;
46	int32_t info_version;
47	uint32_t id;
48	char name[64];
49	char version[64];
50	int32_t reference_count;
51	uint32_t reference_list; /*< Points to kmod_reference_t. /
52	uint32_t address; /*< Where in memory the kext is loaded. /
53	uint32_t size;
54	uint32_t hdr_size;
55	uint32_t start; /*< Address of kmod_start_func_t. /
56	uint32_t stop; /*< Address of kmod_stop_func_t. /
57	} OSX32_kmod_info_t;
58
59	/**
60	* 32-bit darwin kernel module info structure (kmod_info_t).
61	*/
62	#pragma pack(1)
63	typedef struct OSX64_kmod_info
64	{
65	uint64_t next;
66	int32_t info_version;
67	uint32_t id;
68	char name[64];
69	char version[64];
70	int32_t reference_count;
71	uint64_t reference_list; /*< Points to kmod_reference_t. Misaligned, duh. /
72	uint64_t address; /*< Where in memory the kext is loaded. /
73	uint64_t size;
74	uint64_t hdr_size;
75	uint64_t start; /*< Address of kmod_start_func_t. /
76	uint64_t stop; /*< Address of kmod_stop_func_t. /
77	} OSX64_kmod_info_t;
78	#pragma pack()
79
80	/** The value of the info_version field. */
81	#define OSX_KMOD_INFO_VERSION INT32_C(1)
82
83	/** @} */
84
85
86	/**
87	* Linux guest OS digger instance data.
88	*/
89	typedef struct DBGDIGGERDARWIN
90	{
91	/** Whether the information is valid or not.
92	* (For fending off illegal interface method calls.) */
93	bool fValid;
94
95	/** The address of an kernel version string (there are several).
96	* This is set during probing. */
97	DBGFADDRESS AddrKernelVersion;
98	/** Kernel base address.
99	* This is set during probing. */
100	DBGFADDRESS AddrKernel;
101	} DBGDIGGERDARWIN;
102	/** Pointer to the linux guest OS digger instance data. */
103	typedef DBGDIGGERDARWIN *PDBGDIGGERDARWIN;
104
105
106	/*******************************************************************************
107	* Defined Constants And Macros *
108	*******************************************************************************/
109	/** Validates a 32-bit darwin kernel address */
110	#define OSX32_VALID_ADDRESS(Addr) ((Addr) > UINT32_C(0x00001000) && (Addr) < UINT32_C(0xfffff000))
111	/** Validates a 64-bit darwin kernel address */
112	#define OSX64_VALID_ADDRESS(Addr) ((Addr) > UINT64_C(0xffff800000000000) && (Addr) < UINT64_C(0xfffffffffffff000))
113	/** Validates a 32-bit or 64-bit darwin kernel address. */
114	#define OSX_VALID_ADDRESS(a_f64Bits, a_Addr) \
115	((a_f64Bits) ? OSX64_VALID_ADDRESS(a_Addr) : OSX32_VALID_ADDRESS(a_Addr))
116
117	/** AppleOsX on little endian ASCII systems. */
118	#define DIG_DARWIN_MOD_TAG UINT64_C(0x58734f656c707041)
119
120
121	/*******************************************************************************
122	* Internal Functions *
123	*******************************************************************************/
124	static DECLCALLBACK(int) dbgDiggerDarwinInit(PUVM pUVM, void *pvData);
125
126
127	/**
128	* @copydoc DBGFOSREG::pfnQueryInterface
129	*/
130	static DECLCALLBACK(void ) dbgDiggerDarwinQueryInterface(PUVM pUVM, void pvData, DBGFOSINTERFACE enmIf)
131	{
132	return NULL;
133	}
134
135
136	/**
137	* @copydoc DBGFOSREG::pfnQueryVersion
138	*/
139	static DECLCALLBACK(int) dbgDiggerDarwinQueryVersion(PUVM pUVM, void pvData, char pszVersion, size_t cchVersion)
140	{
141	PDBGDIGGERDARWIN pThis = (PDBGDIGGERDARWIN)pvData;
142	Assert(pThis->fValid);
143
144	/*
145	* It's all in the linux banner.
146	*/
147	int rc = DBGFR3MemReadString(pUVM, 0, &pThis->AddrKernelVersion, pszVersion, cchVersion);
148	if (RT_SUCCESS(rc))
149	{
150	char *pszEnd = RTStrEnd(pszVersion, cchVersion);
151	AssertReturn(pszEnd, VERR_BUFFER_OVERFLOW);
152	while ( pszEnd > pszVersion
153	&& RT_C_IS_SPACE(pszEnd[-1]))
154	pszEnd--;
155	*pszEnd = '\0';
156	}
157	else
158	RTStrPrintf(pszVersion, cchVersion, "DBGFR3MemRead -> %Rrc", rc);
159
160	return rc;
161	}
162
163
164	/**
165	* @copydoc DBGFOSREG::pfnTerm
166	*/
167	static DECLCALLBACK(void) dbgDiggerDarwinTerm(PUVM pUVM, void *pvData)
168	{
169	PDBGDIGGERDARWIN pThis = (PDBGDIGGERDARWIN)pvData;
170
171	pThis->fValid = false;
172	}
173
174
175	/**
176	* @copydoc DBGFOSREG::pfnRefresh
177	*/
178	static DECLCALLBACK(int) dbgDiggerDarwinRefresh(PUVM pUVM, void *pvData)
179	{
180	PDBGDIGGERDARWIN pThis = (PDBGDIGGERDARWIN)pvData;
181	NOREF(pThis);
182	Assert(pThis->fValid);
183
184	/*
185	* For now we'll flush and reload everything.
186	*/
187	dbgDiggerDarwinTerm(pUVM, pvData);
188	return dbgDiggerDarwinInit(pUVM, pvData);
189	}
190
191
192	/**
193	* Helper function that validates a segment (or section) name.
194	*
195	* @returns true if valid, false if not.
196	* @param pszName The name string.
197	* @param cbName The size of the string, including terminator.
198	*/
199	static bool dbgDiggerDarwinIsValidSegOrSectName(const char *pszName, size_t cbName)
200	{
201	/* ascii chars */
202	char ch;
203	size_t off = 0;
204	while (off < cbName && (ch = pszName[off]))
205	{
206	if (RT_C_IS_CNTRL(ch) \|\| ch >= 127)
207	return false;
208	off++;
209	}
210
211	/* Not empty nor 100% full. */
212	if (off == 0 \|\| off == cbName)
213	return false;
214
215	/* remainder should be zeros. */
216	while (off < cbName)
217	{
218	if (pszName[off])
219	return false;
220	off++;
221	}
222
223	return true;
224	}
225
226
227	static int dbgDiggerDarwinAddModule(PDBGDIGGERDARWIN pThis, PUVM pUVM, uint64_t uModAddr, const char pszName, bool pf64Bit)
228	{
229	union
230	{
231	uint8_t ab[2 * X86_PAGE_4K_SIZE];
232	mach_header_64_t Hdr64;
233	mach_header_32_t Hdr32;
234	} uBuf;
235
236	/* Read the first page of the image. */
237	DBGFADDRESS ModAddr;
238	int rc = DBGFR3MemRead(pUVM, 0 /idCpu/, DBGFR3AddrFromFlat(pUVM, &ModAddr, uModAddr), uBuf.ab, X86_PAGE_4K_SIZE);
239	if (RT_FAILURE(rc))
240	return rc;
241
242	/* Validate the header. */
243	AssertCompileMembersSameSizeAndOffset(mach_header_64_t, magic, mach_header_32_t, magic);
244	if ( uBuf.Hdr64.magic != IMAGE_MACHO64_SIGNATURE
245	&& uBuf.Hdr32.magic != IMAGE_MACHO32_SIGNATURE)
246	return VERR_INVALID_EXE_SIGNATURE;
247	AssertCompileMembersSameSizeAndOffset(mach_header_64_t, cputype, mach_header_32_t, cputype);
248	bool f64Bit = uBuf.Hdr64.magic == IMAGE_MACHO64_SIGNATURE;
249	if (uBuf.Hdr32.cputype != (f64Bit ? CPU_TYPE_X86_64 : CPU_TYPE_I386))
250	return VERR_LDR_ARCH_MISMATCH;
251	AssertCompileMembersSameSizeAndOffset(mach_header_64_t, filetype, mach_header_32_t, filetype);
252	if ( uBuf.Hdr32.filetype != MH_EXECUTE
253	&& uBuf.Hdr32.filetype != (f64Bit ? MH_KEXT_BUNDLE : MH_OBJECT))
254	return VERR_BAD_EXE_FORMAT;
255	AssertCompileMembersSameSizeAndOffset(mach_header_64_t, ncmds, mach_header_32_t, ncmds);
256	if (uBuf.Hdr32.ncmds > 256)
257	return VERR_BAD_EXE_FORMAT;
258	AssertCompileMembersSameSizeAndOffset(mach_header_64_t, sizeofcmds, mach_header_32_t, sizeofcmds);
259	if (uBuf.Hdr32.sizeofcmds > X86_PAGE_4K_SIZE * 2 - sizeof(mach_header_64_t))
260	return VERR_BAD_EXE_FORMAT;
261
262	/* Do we need to read a 2nd page to get all the load commands? If so, do it. */
263	if (uBuf.Hdr32.sizeofcmds + (f64Bit ? sizeof(mach_header_64_t) : sizeof(mach_header_32_t)) > X86_PAGE_4K_SIZE)
264	{
265	rc = DBGFR3MemRead(pUVM, 0 /idCpu/, DBGFR3AddrFromFlat(pUVM, &ModAddr, uModAddr + X86_PAGE_4K_SIZE),
266	&uBuf.ab[X86_PAGE_4K_SIZE], X86_PAGE_4K_SIZE);
267	if (RT_FAILURE(rc))
268	return rc;
269	}
270
271	/*
272	* Process the load commands.
273	*/
274	RTDBGSEGMENT aSegs[24];
275	uint32_t cSegs = 0;
276	RTUUID Uuid = RTUUID_INITIALIZE_NULL;
277	uint32_t cLeft = uBuf.Hdr32.ncmds;
278	uint32_t cbLeft = uBuf.Hdr32.sizeofcmds;
279	union
280	{
281	uint8_t const *pb;
282	load_command_t const *pGenric;
283	segment_command_32_t const *pSeg32;
284	segment_command_64_t const *pSeg64;
285	section_32_t const *pSect32;
286	section_64_t const *pSect64;
287	symtab_command_t const *pSymTab;
288	uuid_command_t const *pUuid;
289	} uLCmd;
290	uLCmd.pb = &uBuf.ab[f64Bit ? sizeof(mach_header_64_t) : sizeof(mach_header_32_t)];
291
292	while (cLeft-- > 0)
293	{
294	uint32_t const cbCmd = uLCmd.pGenric->cmdsize;
295	if (cbCmd > cbLeft \|\| cbCmd < sizeof(load_command_t))
296	return VERR_BAD_EXE_FORMAT;
297
298	switch (uLCmd.pGenric->cmd)
299	{
300	case LC_SEGMENT_32:
301	if (cbCmd != sizeof(segment_command_32_t) + uLCmd.pSeg32->nsects * sizeof(section_32_t))
302	return VERR_BAD_EXE_FORMAT;
303	if (!dbgDiggerDarwinIsValidSegOrSectName(uLCmd.pSeg32->segname, sizeof(uLCmd.pSeg32->segname)))
304	return VERR_INVALID_NAME;
305	if (!strcmp(uLCmd.pSeg32->segname, "__LINKEDIT"))
306	break; /* This usually is discarded or not loaded at all. */
307	if (cSegs >= RT_ELEMENTS(aSegs))
308	return VERR_BUFFER_OVERFLOW;
309	aSegs[cSegs].Address = uLCmd.pSeg32->vmaddr;
310	aSegs[cSegs].uRva = uLCmd.pSeg32->vmaddr - uModAddr;
311	aSegs[cSegs].cb = uLCmd.pSeg32->vmsize;
312	aSegs[cSegs].fFlags = uLCmd.pSeg32->flags; /* Abusing the flags field here... */
313	aSegs[cSegs].iSeg = cSegs;
314	AssertCompile(RTDBG_SEGMENT_NAME_LENGTH > sizeof(uLCmd.pSeg32->segname));
315	strcpy(aSegs[cSegs].szName, uLCmd.pSeg32->segname);
316	cSegs++;
317	break;
318
319	case LC_SEGMENT_64:
320	if (cbCmd != sizeof(segment_command_64_t) + uLCmd.pSeg64->nsects * sizeof(section_64_t))
321	return VERR_BAD_EXE_FORMAT;
322	if (!dbgDiggerDarwinIsValidSegOrSectName(uLCmd.pSeg64->segname, sizeof(uLCmd.pSeg64->segname)))
323	return VERR_INVALID_NAME;
324	if (!strcmp(uLCmd.pSeg64->segname, "__LINKEDIT"))
325	break; /* This usually is discarded or not loaded at all. */
326	if (cSegs >= RT_ELEMENTS(aSegs))
327	return VERR_BUFFER_OVERFLOW;
328	aSegs[cSegs].Address = uLCmd.pSeg64->vmaddr;
329	aSegs[cSegs].uRva = uLCmd.pSeg64->vmaddr - uModAddr;
330	aSegs[cSegs].cb = uLCmd.pSeg64->vmsize;
331	aSegs[cSegs].fFlags = uLCmd.pSeg64->flags; /* Abusing the flags field here... */
332	aSegs[cSegs].iSeg = cSegs;
333	AssertCompile(RTDBG_SEGMENT_NAME_LENGTH > sizeof(uLCmd.pSeg64->segname));
334	strcpy(aSegs[cSegs].szName, uLCmd.pSeg64->segname);
335	cSegs++;
336	break;
337
338	case LC_UUID:
339	if (cbCmd != sizeof(uuid_command_t))
340	return VERR_BAD_EXE_FORMAT;
341	if (RTUuidIsNull((PCRTUUID)&uLCmd.pUuid->uuid[0]))
342	return VERR_BAD_EXE_FORMAT;
343	memcpy(&Uuid, &uLCmd.pUuid->uuid[0], sizeof(uLCmd.pUuid->uuid));
344	break;
345
346	default:
347	/* Current known max plus a lot of slack. */
348	if (uLCmd.pGenric->cmd > LC_DYLIB_CODE_SIGN_DRS + 32)
349	return VERR_BAD_EXE_FORMAT;
350	break;
351	}
352
353	/* next */
354	cbLeft -= cbCmd;
355	uLCmd.pb += cbCmd;
356	}
357
358	if (cbLeft != 0)
359	return VERR_BAD_EXE_FORMAT;
360
361	/*
362	* Some post processing checks.
363	*/
364	uint32_t iSeg;
365	for (iSeg = 0; iSeg < cSegs; iSeg++)
366	if (aSegs[iSeg].Address == uModAddr)
367	break;
368	if (iSeg >= cSegs)
369	return VERR_ADDRESS_CONFLICT;
370
371	/*
372	* Create a debug module.
373	*/
374	RTDBGMOD hMod;
375	rc = RTDbgModCreateFromMachOImage(&hMod, pszName, NULL, f64Bit ? RTLDRARCH_AMD64 : RTLDRARCH_X86_32, 0 /cbImage/,
376	cSegs, aSegs, &Uuid, DBGFR3AsGetConfig(pUVM), RTDBGMOD_F_NOT_DEFERRED);
377
378	if (RT_FAILURE(rc))
379	{
380	/*
381	* Final fallback is a container module.
382	*/
383	rc = RTDbgModCreate(&hMod, pszName, 0, 0);
384	if (RT_FAILURE(rc))
385	return rc;
386
387	uint64_t uRvaNext = 0;
388	for (iSeg = 0; iSeg < cSegs && RT_SUCCESS(rc); iSeg++)
389	{
390	if ( aSegs[iSeg].uRva > uRvaNext
391	&& aSegs[iSeg].uRva - uRvaNext < _1M)
392	uRvaNext = aSegs[iSeg].uRva;
393	rc = RTDbgModSegmentAdd(hMod, aSegs[iSeg].uRva, aSegs[iSeg].cb, aSegs[iSeg].szName, 0, NULL);
394	if (aSegs[iSeg].cb > 0 && RT_SUCCESS(rc))
395	{
396	char szTmp[RTDBG_SEGMENT_NAME_LENGTH + sizeof("_start")];
397	strcat(strcpy(szTmp, aSegs[iSeg].szName), "_start");
398	rc = RTDbgModSymbolAdd(hMod, szTmp, iSeg, 0 /uRva/, 0 /cb/, 0 /fFlags/, NULL);
399	}
400	uRvaNext += aSegs[iSeg].cb;
401	}
402
403	if (RT_FAILURE(rc))
404	{
405	RTDbgModRelease(hMod);
406	return rc;
407	}
408	}
409
410	/* Tag the module. */
411	rc = RTDbgModSetTag(hMod, DIG_DARWIN_MOD_TAG);
412	AssertRC(rc);
413
414	/*
415	* Link the module.
416	*/
417	RTDBGAS hAs = DBGFR3AsResolveAndRetain(pUVM, DBGF_AS_KERNEL);
418	if (hAs != NIL_RTDBGAS)
419	{
420	uint64_t uRvaNext = 0;
421	uint32_t cLinked = 0;
422	iSeg = cSegs;
423	while (iSeg-- > 0) /* HACK: Map in reverse order to avoid replacing __TEXT. */
424	if (aSegs[iSeg].cb)
425	{
426	/* Find matching segment in the debug module. */
427	uint32_t iDbgSeg = 0;
428	while (iDbgSeg < cSegs)
429	{
430	RTDBGSEGMENT SegInfo;
431	int rc3 = RTDbgModSegmentByIndex(hMod, iDbgSeg, &SegInfo);
432	if (RT_SUCCESS(rc3) && !strcmp(SegInfo.szName, aSegs[iSeg].szName))
433	break;
434	iDbgSeg++;
435	}
436	AssertMsgStmt(iDbgSeg < cSegs, ("%s\n", aSegs[iSeg].szName), continue);
437
438	/* Map it. */
439	int rc2 = RTDbgAsModuleLinkSeg(hAs, hMod, iDbgSeg, aSegs[iSeg].Address, RTDBGASLINK_FLAGS_REPLACE /fFlags/);
440	if (RT_SUCCESS(rc2))
441	cLinked++;
442	else if (RT_SUCCESS(rc))
443	rc = rc2;
444	}
445	if (RT_FAILURE(rc) && cLinked != 0)
446	rc = -rc;
447	}
448	else
449	rc = VERR_INTERNAL_ERROR;
450
451	RTDbgModRelease(hMod);
452	RTDbgAsRelease(hAs);
453
454	if (pf64Bit)
455	*pf64Bit = f64Bit;
456	return rc;
457	}
458
459
460	static bool dbgDiggerDarwinIsValidName(const char *pszName)
461	{
462	char ch;
463	while ((ch = *pszName++) != '\0')
464	{
465	if (ch < 0x20 \|\| ch >= 127)
466	return false;
467	}
468	return true;
469	}
470
471
472	static bool dbgDiggerDarwinIsValidVersion(const char *pszVersion)
473	{
474	char ch;
475	while ((ch = *pszVersion++) != '\0')
476	{
477	if (ch < 0x20 \|\| ch >= 127)
478	return false;
479	}
480	return true;
481	}
482
483
484	/**
485	* @copydoc DBGFOSREG::pfnInit
486	*/
487	static DECLCALLBACK(int) dbgDiggerDarwinInit(PUVM pUVM, void *pvData)
488	{
489	PDBGDIGGERDARWIN pThis = (PDBGDIGGERDARWIN)pvData;
490	Assert(!pThis->fValid);
491
492	/*
493	* Add the kernel module.
494	*/
495	bool f64Bit;
496	int rc = dbgDiggerDarwinAddModule(pThis, pUVM, pThis->AddrKernel.FlatPtr, "mach_kernel", &f64Bit);
497	if (RT_SUCCESS(rc))
498	{
499	/*
500	* The list of modules can be found at the 'kmod' symbol, that means
501	* that we currently require some kind of symbol file for the kernel
502	* to be loaded at this point.
503	*
504	* Note! Could also use the 'gLoadedKextSummaries', but I don't think
505	* it's any easier to find without any kernel map than 'kmod'.
506	*/
507	RTDBGSYMBOL SymInfo;
508	rc = DBGFR3AsSymbolByName(pUVM, DBGF_AS_KERNEL, "mach_kernel!kmod", &SymInfo, NULL);
509	if (RT_FAILURE(rc))
510	rc = DBGFR3AsSymbolByName(pUVM, DBGF_AS_KERNEL, "mach_kernel!_kmod", &SymInfo, NULL);
511	if (RT_SUCCESS(rc))
512	{
513	DBGFADDRESS AddrModInfo;
514	DBGFR3AddrFromFlat(pUVM, &AddrModInfo, SymInfo.Value);
515
516	/* Read the variable. */
517	RTUINT64U uKmodValue = { 0 };
518	if (f64Bit)
519	rc = DBGFR3MemRead(pUVM, 0 /idCpu/, &AddrModInfo, &uKmodValue.u, sizeof(uKmodValue.u));
520	else
521	rc = DBGFR3MemRead (pUVM, 0 /idCpu/, &AddrModInfo, &uKmodValue.s.Lo, sizeof(uKmodValue.s.Lo));
522	if (RT_SUCCESS(rc))
523	{
524	DBGFR3AddrFromFlat(pUVM, &AddrModInfo, uKmodValue.u);
525
526	/* Walk the list of modules. */
527	uint32_t cIterations = 0;
528	while (AddrModInfo.FlatPtr != 0)
529	{
530	/* Some extra loop conditions... */
531	if (!OSX_VALID_ADDRESS(f64Bit, AddrModInfo.FlatPtr))
532	{
533	Log(("OSXDig: Invalid kmod_info pointer: %RGv\n", AddrModInfo.FlatPtr));
534	break;
535	}
536	if (AddrModInfo.FlatPtr == uKmodValue.u && cIterations != 0)
537	{
538	Log(("OSXDig: kmod_info list looped back to the start.\n"));
539	break;
540	}
541	if (cIterations++ >= 2048)
542	{
543	Log(("OSXDig: Too many mod_info loops (%u)\n", cIterations));
544	break;
545	}
546
547	/*
548	* Read the kmod_info_t structure.
549	*/
550	union
551	{
552	OSX64_kmod_info_t Info64;
553	OSX32_kmod_info_t Info32;
554	} uMod;
555	RT_ZERO(uMod);
556	rc = DBGFR3MemRead(pUVM, 0 /idCpu/, &AddrModInfo, &uMod,
557	f64Bit ? sizeof(uMod.Info64) : sizeof(uMod.Info32));
558	if (RT_FAILURE(rc))
559	{
560	Log(("OSXDig: Error reading kmod_info structure at %RGv: %Rrc\n", AddrModInfo.FlatPtr, rc));
561	break;
562	}
563
564	/*
565	* Validate the kmod_info_t structure.
566	*/
567	int32_t iInfoVer = f64Bit ? uMod.Info64.info_version : uMod.Info32.info_version;
568	if (iInfoVer != OSX_KMOD_INFO_VERSION)
569	{
570	Log(("OSXDig: kmod_info @%RGv: Bad info_version %d\n", AddrModInfo.FlatPtr, iInfoVer));
571	break;
572	}
573
574	const char *pszName = f64Bit ? uMod.Info64.name : uMod.Info32.name;
575	if ( !*pszName
576	\|\| !RTStrEnd(pszName, sizeof(uMod.Info64.name))
577	\|\| !dbgDiggerDarwinIsValidName(pszName) )
578	{
579	Log(("OSXDig: kmod_info @%RGv: Bad name '%.*s'\n", AddrModInfo.FlatPtr,
580	sizeof(uMod.Info64.name), pszName));
581	break;
582	}
583
584	const char *pszVersion = f64Bit ? uMod.Info64.version : uMod.Info32.version;
585	if ( !RTStrEnd(pszVersion, sizeof(uMod.Info64.version))
586	\|\| !dbgDiggerDarwinIsValidVersion(pszVersion) )
587	{
588	Log(("OSXDig: kmod_info @%RGv: Bad version '%.*s'\n", AddrModInfo.FlatPtr,
589	sizeof(uMod.Info64.version), pszVersion));
590	break;
591	}
592
593	int32_t cRefs = f64Bit ? uMod.Info64.reference_count : uMod.Info32.reference_count;
594	if (cRefs < -1 \|\| cRefs > 16384)
595	{
596	Log(("OSXDig: kmod_info @%RGv: Bad reference_count %d\n", AddrModInfo.FlatPtr, cRefs));
597	break;
598	}
599
600	uint64_t uImageAddr = f64Bit ? uMod.Info64.address : uMod.Info32.address;
601	if (!OSX_VALID_ADDRESS(f64Bit, uImageAddr))
602	{
603	Log(("OSXDig: kmod_info @%RGv: Bad address %#llx\n", AddrModInfo.FlatPtr, uImageAddr));
604	break;
605	}
606
607	uint64_t cbImage = f64Bit ? uMod.Info64.size : uMod.Info32.size;
608	if (cbImage > 64U*_1M)
609	{
610	Log(("OSXDig: kmod_info @%RGv: Bad size %#llx\n", AddrModInfo.FlatPtr, cbImage));
611	break;
612	}
613
614	uint64_t cbHdr = f64Bit ? uMod.Info64.hdr_size : uMod.Info32.hdr_size;
615	if (cbHdr > 16U*_1M)
616	{
617	Log(("OSXDig: kmod_info @%RGv: Bad hdr_size %#llx\n", AddrModInfo.FlatPtr, cbHdr));
618	break;
619	}
620
621	uint64_t uStartAddr = f64Bit ? uMod.Info64.start : uMod.Info32.start;
622	if (!uStartAddr && !OSX_VALID_ADDRESS(f64Bit, uStartAddr))
623	{
624	Log(("OSXDig: kmod_info @%RGv: Bad start function %#llx\n", AddrModInfo.FlatPtr, uStartAddr));
625	break;
626	}
627
628	uint64_t uStopAddr = f64Bit ? uMod.Info64.stop : uMod.Info32.stop;
629	if (!uStopAddr && !OSX_VALID_ADDRESS(f64Bit, uStopAddr))
630	{
631	Log(("OSXDig: kmod_info @%RGv: Bad stop function %#llx\n", AddrModInfo.FlatPtr, uStopAddr));
632	break;
633	}
634
635	/*
636	* Try add the module.
637	*/
638	Log(("OSXDig: kmod_info @%RGv: '%s' ver '%s', image @%#llx LB %#llx cbHdr=%#llx\n", AddrModInfo.FlatPtr,
639	pszName, pszVersion, uImageAddr, cbImage, cbHdr));
640	rc = dbgDiggerDarwinAddModule(pThis, pUVM, uImageAddr, pszName, NULL);
641
642
643	/*
644	* Advance to the next kmod_info entry.
645	*/
646	DBGFR3AddrFromFlat(pUVM, &AddrModInfo, f64Bit ? uMod.Info64.next : uMod.Info32.next);
647	}
648	}
649	else
650	Log(("OSXDig: Error reading the 'kmod' variable: %Rrc\n", rc));
651	}
652	else
653	Log(("OSXDig: Failed to locate the 'kmod' variable in mach_kernel.\n"));
654
655	pThis->fValid = true;
656	return VINF_SUCCESS;
657	}
658
659	return rc;
660	}
661
662
663	/**
664	* @copydoc DBGFOSREG::pfnProbe
665	*/
666	static DECLCALLBACK(bool) dbgDiggerDarwinProbe(PUVM pUVM, void *pvData)
667	{
668	PDBGDIGGERDARWIN pThis = (PDBGDIGGERDARWIN)pvData;
669
670	/*
671	* Look for a section + segment combo that normally only occures in
672	* mach_kernel. Follow it up with probing of the rest of the executable
673	* header. We must search a largish area because the more recent versions
674	* of darwin have random load address for security raisins.
675	*/
676	static struct { uint64_t uStart, uEnd; } const s_aRanges[] =
677	{
678	/* 64-bit: */
679	{ UINT64_C(0xffffff8000000000), UINT64_C(0xffffff81ffffffff), },
680
681	/* 32-bit - always search for this because of the hybrid 32-bit kernel
682	with cpu in long mode that darwin used for a number of versions. */
683	{ UINT64_C(0x00001000), UINT64_C(0x0ffff000), }
684	};
685	for (unsigned iRange = DBGFR3CpuGetMode(pUVM, 0 /idCpu/) != CPUMMODE_LONG;
686	iRange < RT_ELEMENTS(s_aRanges);
687	iRange++)
688	{
689	DBGFADDRESS KernelAddr;
690	for (DBGFR3AddrFromFlat(pUVM, &KernelAddr, s_aRanges[iRange].uStart);
691	KernelAddr.FlatPtr < s_aRanges[iRange].uEnd;
692	KernelAddr.FlatPtr += X86_PAGE_4K_SIZE)
693	{
694	static const uint8_t s_abNeedle[16 + 16] =
695	{
696	'_','_','t','e','x','t', 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* section_32_t::sectname */
697	'_','_','K','L','D', 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* section_32_t::segname. */
698	};
699
700	int rc = DBGFR3MemScan(pUVM, 0 /idCpu/, &KernelAddr, s_aRanges[iRange].uEnd - KernelAddr.FlatPtr,
701	1, s_abNeedle, sizeof(s_abNeedle), &KernelAddr);
702	if (RT_FAILURE(rc))
703	break;
704	DBGFR3AddrSub(&KernelAddr, KernelAddr.FlatPtr & X86_PAGE_4K_OFFSET_MASK);
705
706	/*
707	* Read the first page of the image and check the headers.
708	*/
709	union
710	{
711	uint8_t ab[X86_PAGE_4K_SIZE];
712	mach_header_64_t Hdr64;
713	mach_header_32_t Hdr32;
714	} uBuf;
715	rc = DBGFR3MemRead(pUVM, 0 /idCpu/, &KernelAddr, uBuf.ab, X86_PAGE_4K_SIZE);
716	if (RT_FAILURE(rc))
717	continue;
718	AssertCompileMembersSameSizeAndOffset(mach_header_64_t, magic, mach_header_32_t, magic);
719	if ( uBuf.Hdr64.magic != IMAGE_MACHO64_SIGNATURE
720	&& uBuf.Hdr32.magic != IMAGE_MACHO32_SIGNATURE)
721	continue;
722	AssertCompileMembersSameSizeAndOffset(mach_header_64_t, cputype, mach_header_32_t, cputype);
723	bool f64Bit = uBuf.Hdr64.magic == IMAGE_MACHO64_SIGNATURE;
724	if (uBuf.Hdr32.cputype != (f64Bit ? CPU_TYPE_X86_64 : CPU_TYPE_I386))
725	continue;
726	AssertCompileMembersSameSizeAndOffset(mach_header_64_t, filetype, mach_header_32_t, filetype);
727	if (uBuf.Hdr32.filetype != MH_EXECUTE)
728	continue;
729	AssertCompileMembersSameSizeAndOffset(mach_header_64_t, ncmds, mach_header_32_t, ncmds);
730	if (uBuf.Hdr32.ncmds > 256)
731	continue;
732	AssertCompileMembersSameSizeAndOffset(mach_header_64_t, sizeofcmds, mach_header_32_t, sizeofcmds);
733	if (uBuf.Hdr32.sizeofcmds > X86_PAGE_4K_SIZE * 2 - sizeof(mach_header_64_t))
734	continue;
735
736	/* Seems good enough for now.
737
738	If the above causes false positives, check the segments and make
739	sure there is a kernel version string in the right one. */
740	pThis->AddrKernel = KernelAddr;
741
742	/*
743	* Finally, find the kernel version string.
744	*/
745	rc = DBGFR3MemScan(pUVM, 0 /idCpu/, &KernelAddr, 32*_1M, 1, RT_STR_TUPLE("Darwin Kernel Version"),
746	&pThis->AddrKernelVersion);
747	if (RT_FAILURE(rc))
748	DBGFR3AddrFromFlat(pUVM, &pThis->AddrKernelVersion, 0);
749	return true;
750	}
751	}
752	return false;
753	}
754
755
756	/**
757	* @copydoc DBGFOSREG::pfnDestruct
758	*/
759	static DECLCALLBACK(void) dbgDiggerDarwinDestruct(PUVM pUVM, void *pvData)
760	{
761
762	}
763
764
765	/**
766	* @copydoc DBGFOSREG::pfnConstruct
767	*/
768	static DECLCALLBACK(int) dbgDiggerDarwinConstruct(PUVM pUVM, void *pvData)
769	{
770	return VINF_SUCCESS;
771	}
772
773
774	const DBGFOSREG g_DBGDiggerDarwin =
775	{
776	/* .u32Magic = */ DBGFOSREG_MAGIC,
777	/* .fFlags = */ 0,
778	/* .cbData = */ sizeof(DBGDIGGERDARWIN),
779	/* .szName = */ "Darwin",
780	/* .pfnConstruct = */ dbgDiggerDarwinConstruct,
781	/* .pfnDestruct = */ dbgDiggerDarwinDestruct,
782	/* .pfnProbe = */ dbgDiggerDarwinProbe,
783	/* .pfnInit = */ dbgDiggerDarwinInit,
784	/* .pfnRefresh = */ dbgDiggerDarwinRefresh,
785	/* .pfnTerm = */ dbgDiggerDarwinTerm,
786	/* .pfnQueryVersion = */ dbgDiggerDarwinQueryVersion,
787	/* .pfnQueryInterface = */ dbgDiggerDarwinQueryInterface,
788	/* .u32EndMagic = */ DBGFOSREG_MAGIC
789	};
790

Note: See TracBrowser for help on using the repository browser.

source: vbox/trunk/src/VBox/Debugger/DBGPlugInDarwin.cpp@ 53369

Download in other formats: