ldrELFRelocatable.cpp.h@ 39070

Last change on this file since 39070 was 39032, checked in by vboxsync, 13 years ago
IPRT: Fixed unused variable warnings.
Property svn:eol-style set to `native` Property svn:keywords set to `Id`
File size: 45.3 KB

Line
1	/* $Id: ldrELFRelocatable.cpp.h 39032 2011-10-19 11:08:50Z vboxsync $ */
2	/** @file
3	* IPRT - Binary Image Loader, Template for ELF Relocatable Images.
4	*/
5
6	/*
7	* Copyright (C) 2006-2007 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	* The contents of this file may alternatively be used under the terms
18	* of the Common Development and Distribution License Version 1.0
19	* (CDDL) only, as it comes in the "COPYING.CDDL" file of the
20	* VirtualBox OSE distribution, in which case the provisions of the
21	* CDDL are applicable instead of those of the GPL.
22	*
23	* You may elect to license modified versions of this file under the
24	* terms and conditions of either the GPL or the CDDL or both.
25	*/
26
27
28	/*******************************************************************************
29	* Defined Constants And Macros *
30	*******************************************************************************/
31	#if ELF_MODE == 32
32	#define RTLDRELF_NAME(name) rtldrELF32##name
33	#define RTLDRELF_SUFF(name) name##32
34	#define RTLDRELF_MID(pre,suff) pre##32##suff
35	#define FMT_ELF_ADDR "%08RX32"
36	#define FMT_ELF_HALF "%04RX16"
37	#define FMT_ELF_OFF "%08RX32"
38	#define FMT_ELF_SIZE "%08RX32"
39	#define FMT_ELF_SWORD "%RI32"
40	#define FMT_ELF_WORD "%08RX32"
41	#define FMT_ELF_XWORD "%08RX32"
42	#define FMT_ELF_SXWORD "%RI32"
43
44	#elif ELF_MODE == 64
45	#define RTLDRELF_NAME(name) rtldrELF64##name
46	#define RTLDRELF_SUFF(name) name##64
47	#define RTLDRELF_MID(pre,suff) pre##64##suff
48	#define FMT_ELF_ADDR "%016RX64"
49	#define FMT_ELF_HALF "%04RX16"
50	#define FMT_ELF_SHALF "%RI16"
51	#define FMT_ELF_OFF "%016RX64"
52	#define FMT_ELF_SIZE "%016RX64"
53	#define FMT_ELF_SWORD "%RI32"
54	#define FMT_ELF_WORD "%08RX32"
55	#define FMT_ELF_XWORD "%016RX64"
56	#define FMT_ELF_SXWORD "%RI64"
57	#endif
58
59	#define Elf_Ehdr RTLDRELF_MID(Elf,_Ehdr)
60	#define Elf_Phdr RTLDRELF_MID(Elf,_Phdr)
61	#define Elf_Shdr RTLDRELF_MID(Elf,_Shdr)
62	#define Elf_Sym RTLDRELF_MID(Elf,_Sym)
63	#define Elf_Rel RTLDRELF_MID(Elf,_Rel)
64	#define Elf_Rela RTLDRELF_MID(Elf,_Rela)
65	#define Elf_Nhdr RTLDRELF_MID(Elf,_Nhdr)
66	#define Elf_Dyn RTLDRELF_MID(Elf,_Dyn)
67	#define Elf_Addr RTLDRELF_MID(Elf,_Addr)
68	#define Elf_Half RTLDRELF_MID(Elf,_Half)
69	#define Elf_Off RTLDRELF_MID(Elf,_Off)
70	#define Elf_Size RTLDRELF_MID(Elf,_Size)
71	#define Elf_Sword RTLDRELF_MID(Elf,_Sword)
72	#define Elf_Word RTLDRELF_MID(Elf,_Word)
73
74	#define RTLDRMODELF RTLDRELF_MID(RTLDRMODELF,RT_NOTHING)
75	#define PRTLDRMODELF RTLDRELF_MID(PRTLDRMODELF,RT_NOTHING)
76
77	#define ELF_R_SYM(info) RTLDRELF_MID(ELF,_R_SYM)(info)
78	#define ELF_R_TYPE(info) RTLDRELF_MID(ELF,_R_TYPE)(info)
79	#define ELF_R_INFO(sym, type) RTLDRELF_MID(ELF,_R_INFO)(sym, type)
80
81	#define ELF_ST_BIND(info) RTLDRELF_MID(ELF,_ST_BIND)(info)
82
83
84
85	/*******************************************************************************
86	* Structures and Typedefs *
87	*******************************************************************************/
88	/**
89	* The ELF loader structure.
90	*/
91	typedef struct RTLDRMODELF
92	{
93	/** Core module structure. */
94	RTLDRMODINTERNAL Core;
95	/** Pointer to the reader instance. */
96	PRTLDRREADER pReader;
97	/** Pointer to readonly mapping of the image bits.
98	* This mapping is provided by the pReader. */
99	const void *pvBits;
100
101	/** The ELF header. */
102	Elf_Ehdr Ehdr;
103	/** Pointer to our copy of the section headers.
104	* The virtual addresses in this array is the 0 based assignments we've given the image.
105	* Not valid if the image is DONE. */
106	Elf_Shdr *paShdrs;
107	/** The size of the loaded image. */
108	size_t cbImage;
109
110	/** The symbol section index. */
111	unsigned iSymSh;
112	/** Number of symbols in the table. */
113	unsigned cSyms;
114	/** Pointer to symbol table within RTLDRMODELF::pvBits. */
115	const Elf_Sym *paSyms;
116
117	/** The string section index. */
118	unsigned iStrSh;
119	/** Size of the string table. */
120	unsigned cbStr;
121	/** Pointer to string table within RTLDRMODELF::pvBits. */
122	const char *pStr;
123	} RTLDRMODELF, *PRTLDRMODELF;
124
125
126	/**
127	* Maps the image bits into memory and resolve pointers into it.
128	*
129	* @returns iprt status code.
130	* @param pModElf The ELF loader module instance data.
131	* @param fNeedsBits Set if we actually need the pvBits member.
132	* If we don't, we can simply read the string and symbol sections, thus saving memory.
133	*/
134	static int RTLDRELF_NAME(MapBits)(PRTLDRMODELF pModElf, bool fNeedsBits)
135	{
136	NOREF(fNeedsBits);
137	if (pModElf->pvBits)
138	return VINF_SUCCESS;
139	int rc = pModElf->pReader->pfnMap(pModElf->pReader, &pModElf->pvBits);
140	if (RT_SUCCESS(rc))
141	{
142	const uint8_t pu8 = (const uint8_t )pModElf->pvBits;
143	pModElf->paSyms = (const Elf_Sym *)(pu8 + pModElf->paShdrs[pModElf->iSymSh].sh_offset);
144	pModElf->pStr = (const char *)(pu8 + pModElf->paShdrs[pModElf->iStrSh].sh_offset);
145	}
146	return rc;
147	}
148
149
150	/**
151	* Get the symbol and symbol value.
152	*
153	* @returns iprt status code.
154	* @param pModElf The ELF loader module instance data.
155	* @param BaseAddr The base address which the module is being fixedup to.
156	* @param pfnGetImport The callback function to use to resolve imports (aka unresolved externals).
157	* @param pvUser User argument to pass to the callback.
158	* @param iSym The symbol to get.
159	* @param ppSym Where to store the symbol pointer on success. (read only)
160	* @param pSymValue Where to store the symbol value on success.
161	*/
162	static int RTLDRELF_NAME(Symbol)(PRTLDRMODELF pModElf, Elf_Addr BaseAddr, PFNRTLDRIMPORT pfnGetImport, void *pvUser,
163	Elf_Size iSym, const Elf_Sym *ppSym, Elf_Addr pSymValue)
164	{
165	/*
166	* Validate and find the symbol.
167	*/
168	if (iSym >= pModElf->cSyms)
169	{
170	AssertMsgFailed(("iSym=%d is an invalid symbol index!\n", iSym));
171	return VERR_LDRELF_INVALID_SYMBOL_INDEX;
172	}
173	const Elf_Sym *pSym = &pModElf->paSyms[iSym];
174	*ppSym = pSym;
175
176	if (pSym->st_name >= pModElf->cbStr)
177	{
178	AssertMsgFailed(("iSym=%d st_name=%d str sh_size=%d\n", iSym, pSym->st_name, pModElf->cbStr));
179	return VERR_LDRELF_INVALID_SYMBOL_NAME_OFFSET;
180	}
181	const char *pszName = ELF_STR(pModElf, pSym->st_name);
182
183	/*
184	* Determine the symbol value.
185	*
186	* Symbols needs different treatment depending on which section their are in.
187	* Undefined and absolute symbols goes into special non-existing sections.
188	*/
189	switch (pSym->st_shndx)
190	{
191	/*
192	* Undefined symbol, needs resolving.
193	*
194	* Since ELF has no generic concept of importing from specific module (the OS/2 ELF format
195	* has but that's a OS extension and only applies to programs and dlls), we'll have to ask
196	* the resolver callback to do a global search.
197	*/
198	case SHN_UNDEF:
199	{
200	/* Try to resolve the symbol. */
201	RTUINTPTR Value;
202	int rc = pfnGetImport(&pModElf->Core, "", pszName, ~0, &Value, pvUser);
203	if (RT_FAILURE(rc))
204	{
205	AssertMsgFailed(("Failed to resolve '%s' rc=%Rrc\n", pszName, rc));
206	return rc;
207	}
208	*pSymValue = (Elf_Addr)Value;
209	if ((RTUINTPTR)*pSymValue != Value)
210	{
211	AssertMsgFailed(("Symbol value overflowed! '%s'\n", pszName));
212	return VERR_SYMBOL_VALUE_TOO_BIG;
213	}
214
215	Log2(("rtldrELF: #%-3d - UNDEF " FMT_ELF_ADDR " '%s'\n", iSym, *pSymValue, pszName));
216	break;
217	}
218
219	/*
220	* Absolute symbols needs no fixing since they are, well, absolute.
221	*/
222	case SHN_ABS:
223	*pSymValue = pSym->st_value;
224	Log2(("rtldrELF: #%-3d - ABS " FMT_ELF_ADDR " '%s'\n", iSym, *pSymValue, pszName));
225	break;
226
227	/*
228	* All other symbols are addressed relative to their section and need to be fixed up.
229	*/
230	default:
231	if (pSym->st_shndx >= pModElf->Ehdr.e_shnum)
232	{
233	/* what about common symbols? */
234	AssertMsg(pSym->st_shndx < pModElf->Ehdr.e_shnum,
235	("iSym=%d st_shndx=%d e_shnum=%d pszName=%s\n", iSym, pSym->st_shndx, pModElf->Ehdr.e_shnum, pszName));
236	return VERR_BAD_EXE_FORMAT;
237	}
238	*pSymValue = pSym->st_value + pModElf->paShdrs[pSym->st_shndx].sh_addr + BaseAddr;
239	Log2(("rtldrELF: #%-3d - %5d " FMT_ELF_ADDR " '%s'\n", iSym, pSym->st_shndx, *pSymValue, pszName));
240	break;
241	}
242
243	return VINF_SUCCESS;
244	}
245
246
247	/**
248	* Applies the fixups for a sections.
249	*
250	* @returns iprt status code.
251	* @param pModElf The ELF loader module instance data.
252	* @param BaseAddr The base address which the module is being fixedup to.
253	* @param pfnGetImport The callback function to use to resolve imports (aka unresolved externals).
254	* @param pvUser User argument to pass to the callback.
255	* @param SecAddr The section address. This is the address the relocations are relative to.
256	* @param cbSec The section size. The relocations must be inside this.
257	* @param pu8SecBaseR Where we read section bits from.
258	* @param pu8SecBaseW Where we write section bits to.
259	* @param pvRelocs Pointer to where we read the relocations from.
260	* @param cbRelocs Size of the relocations.
261	*/
262	static int RTLDRELF_NAME(RelocateSection)(PRTLDRMODELF pModElf, Elf_Addr BaseAddr, PFNRTLDRIMPORT pfnGetImport, void *pvUser,
263	const Elf_Addr SecAddr, Elf_Size cbSec, const uint8_t pu8SecBaseR, uint8_t pu8SecBaseW,
264	const void *pvRelocs, Elf_Size cbRelocs)
265	{
266	/*
267	* Iterate the relocations.
268	* The relocations are stored in an array of Elf32_Rel records and covers the entire relocation section.
269	*/
270	const Elf_Reloc paRels = (const Elf_Reloc )pvRelocs;
271	const unsigned iRelMax = (unsigned)(cbRelocs / sizeof(paRels[0]));
272	AssertMsgReturn(iRelMax == cbRelocs / sizeof(paRels[0]), (FMT_ELF_SIZE "\n", cbRelocs / sizeof(paRels[0])), VERR_IMAGE_TOO_BIG);
273	for (unsigned iRel = 0; iRel < iRelMax; iRel++)
274	{
275	/*
276	* Get the symbol.
277	*/
278	const Elf_Sym *pSym;
279	Elf_Addr SymValue = 0; /* shut up gcc-4 */
280	int rc = RTLDRELF_NAME(Symbol)(pModElf, BaseAddr, pfnGetImport, pvUser, ELF_R_SYM(paRels[iRel].r_info), &pSym, &SymValue);
281	if (RT_FAILURE(rc))
282	return rc;
283
284	Log3(("rtldrELF: " FMT_ELF_ADDR " %02x %06x - " FMT_ELF_ADDR " %3d %02x %s\n",
285	paRels[iRel].r_offset, ELF_R_TYPE(paRels[iRel].r_info), (unsigned)ELF_R_SYM(paRels[iRel].r_info),
286	SymValue, (unsigned)pSym->st_shndx, pSym->st_info, ELF_STR(pModElf, pSym->st_name)));
287
288	/*
289	* Apply the fixup.
290	*/
291	AssertMsgReturn(paRels[iRel].r_offset < cbSec, (FMT_ELF_ADDR " " FMT_ELF_SIZE "\n", paRels[iRel].r_offset, cbSec), VERR_LDRELF_INVALID_RELOCATION_OFFSET);
292	#if ELF_MODE == 32
293	const Elf_Addr pAddrR = (const Elf_Addr )(pu8SecBaseR + paRels[iRel].r_offset); /* Where to read the addend. */
294	#endif
295	Elf_Addr pAddrW = (Elf_Addr )(pu8SecBaseW + paRels[iRel].r_offset); /* Where to write the fixup. */
296	switch (ELF_R_TYPE(paRels[iRel].r_info))
297	{
298	#if ELF_MODE == 32
299	/*
300	* Absolute addressing.
301	*/
302	case R_386_32:
303	{
304	const Elf_Addr Value = SymValue + *pAddrR;
305	(uint32_t )pAddrW = Value;
306	Log4((FMT_ELF_ADDR": R_386_32 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n",
307	SecAddr + paRels[iRel].r_offset + BaseAddr, Value, SymValue));
308	break;
309	}
310
311	/*
312	* PC relative addressing.
313	*/
314	case R_386_PC32:
315	{
316	const Elf_Addr SourceAddr = SecAddr + paRels[iRel].r_offset + BaseAddr; /* Where the source really is. */
317	const Elf_Addr Value = SymValue + (uint32_t )pAddrR - SourceAddr;
318	(uint32_t )pAddrW = Value;
319	Log4((FMT_ELF_ADDR": R_386_PC32 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n",
320	SourceAddr, Value, SymValue));
321	break;
322	}
323
324	/* ignore */
325	case R_386_NONE:
326	break;
327
328	#elif ELF_MODE == 64
329
330	/*
331	* Absolute addressing
332	*/
333	case R_X86_64_64:
334	{
335	const Elf_Addr Value = SymValue + paRels[iRel].r_addend;
336	(uint64_t )pAddrW = Value;
337	Log4((FMT_ELF_ADDR": R_X86_64_64 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n",
338	SecAddr + paRels[iRel].r_offset + BaseAddr, Value, SymValue));
339	break;
340	}
341
342	/*
343	* Truncated 32-bit value (zero-extendedable to the 64-bit value).
344	*/
345	case R_X86_64_32:
346	{
347	const Elf_Addr Value = SymValue + paRels[iRel].r_addend;
348	(uint32_t )pAddrW = (uint32_t)Value;
349	Log4((FMT_ELF_ADDR": R_X86_64_32 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n",
350	SecAddr + paRels[iRel].r_offset + BaseAddr, Value, SymValue));
351	AssertMsgReturn((Elf_Addr)(uint32_t )pAddrW == Value, ("Value=" FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG);
352	break;
353	}
354
355	/*
356	* Truncated 32-bit value (sign-extendedable to the 64-bit value).
357	*/
358	case R_X86_64_32S:
359	{
360	const Elf_Addr Value = SymValue + paRels[iRel].r_addend;
361	(int32_t )pAddrW = (int32_t)Value;
362	Log4((FMT_ELF_ADDR": R_X86_64_32S Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n",
363	SecAddr + paRels[iRel].r_offset + BaseAddr, Value, SymValue));
364	AssertMsgReturn((Elf_Addr)(int32_t )pAddrW == Value, ("Value=" FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG); /** @todo check the sign-extending here. */
365	break;
366	}
367
368	/*
369	* PC relative addressing.
370	*/
371	case R_X86_64_PC32:
372	{
373	const Elf_Addr SourceAddr = SecAddr + paRels[iRel].r_offset + BaseAddr; /* Where the source really is. */
374	const Elf_Addr Value = SymValue + paRels[iRel].r_addend - SourceAddr;
375	(int32_t )pAddrW = (int32_t)Value;
376	Log4((FMT_ELF_ADDR": R_X86_64_PC32 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n",
377	SourceAddr, Value, SymValue));
378	AssertMsgReturn((Elf_Addr)(int32_t )pAddrW == Value, ("Value=" FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG); /** @todo check the sign-extending here. */
379	break;
380	}
381
382	/* ignore */
383	case R_X86_64_NONE:
384	break;
385	#endif
386
387	default:
388	AssertMsgFailed(("Unknown relocation type: %d (iRel=%d iRelMax=%d)\n",
389	ELF_R_TYPE(paRels[iRel].r_info), iRel, iRelMax));
390	return VERR_LDRELF_RELOCATION_NOT_SUPPORTED;
391	}
392	}
393
394	return VINF_SUCCESS;
395	}
396
397
398
399	/** @copydoc RTLDROPS::pfnClose */
400	static DECLCALLBACK(int) RTLDRELF_NAME(Close)(PRTLDRMODINTERNAL pMod)
401	{
402	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
403
404	if (pModElf->paShdrs)
405	{
406	RTMemFree(pModElf->paShdrs);
407	pModElf->paShdrs = NULL;
408	}
409
410	if (pModElf->pReader)
411	{
412	pModElf->pReader->pfnDestroy(pModElf->pReader);
413	pModElf->pReader = NULL;
414	}
415
416	pModElf->pvBits = NULL;
417
418	return VINF_SUCCESS;
419	}
420
421
422	/** @copydoc RTLDROPS::Done */
423	static DECLCALLBACK(int) RTLDRELF_NAME(Done)(PRTLDRMODINTERNAL pMod)
424	{
425	//PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
426	/** @todo Have to think more about this .... */
427	return -1;
428	}
429
430
431	/** @copydoc RTLDROPS::EnumSymbols */
432	static DECLCALLBACK(int) RTLDRELF_NAME(EnumSymbols)(PRTLDRMODINTERNAL pMod, unsigned fFlags, const void *pvBits, RTUINTPTR BaseAddress,
433	PFNRTLDRENUMSYMS pfnCallback, void *pvUser)
434	{
435	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
436
437	/*
438	* Validate the input.
439	*/
440	Elf_Addr BaseAddr = (Elf_Addr)BaseAddress;
441	AssertMsgReturn((RTUINTPTR)BaseAddr == BaseAddress, ("#RTptr", BaseAddress), VERR_IMAGE_BASE_TOO_HIGH);
442
443	/*
444	* Make sure we've got the string and symbol tables. (We don't need the pvBits.)
445	*/
446	int rc = RTLDRELF_NAME(MapBits)(pModElf, false);
447	if (RT_FAILURE(rc))
448	return rc;
449
450	/*
451	* Enumerate the symbol table.
452	*/
453	const Elf_Sym *paSyms = pModElf->paSyms;
454	unsigned cSyms = pModElf->cSyms;
455	for (unsigned iSym = 1; iSym < cSyms; iSym++)
456	{
457	/*
458	* Skip imports (undefined).
459	*/
460	if (paSyms[iSym].st_shndx != SHN_UNDEF)
461	{
462	/*
463	* Calc value and get name.
464	*/
465	Elf_Addr Value;
466	if (paSyms[iSym].st_shndx == SHN_ABS)
467	/* absolute symbols are not subject to any relocation. */
468	Value = paSyms[iSym].st_value;
469	else if (paSyms[iSym].st_shndx < pModElf->Ehdr.e_shnum)
470	/* relative to the section. */
471	Value = BaseAddr + paSyms[iSym].st_value + pModElf->paShdrs[paSyms[iSym].st_shndx].sh_addr;
472	else
473	{
474	AssertMsgFailed(("Arg! paSyms[%u].st_shndx=" FMT_ELF_HALF "\n", iSym, paSyms[iSym].st_shndx));
475	return VERR_BAD_EXE_FORMAT;
476	}
477	const char *pszName = ELF_STR(pModElf, paSyms[iSym].st_name);
478	if ( (pszName && *pszName)
479	&& ( (fFlags & RTLDR_ENUM_SYMBOL_FLAGS_ALL)
480	\|\| ELF_ST_BIND(paSyms[iSym].st_info) == STB_GLOBAL)
481	)
482	{
483	/*
484	* Call back.
485	*/
486	AssertMsgReturn(Value == (RTUINTPTR)Value, (FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG);
487	rc = pfnCallback(pMod, pszName, ~0, (RTUINTPTR)Value, pvUser);
488	if (rc)
489	return rc;
490	}
491	}
492	}
493
494	return VINF_SUCCESS;
495	}
496
497
498	/** @copydoc RTLDROPS::GetImageSize */
499	static DECLCALLBACK(size_t) RTLDRELF_NAME(GetImageSize)(PRTLDRMODINTERNAL pMod)
500	{
501	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
502
503	return pModElf->cbImage;
504	}
505
506
507	/** @copydoc RTLDROPS::GetBits */
508	static DECLCALLBACK(int) RTLDRELF_NAME(GetBits)(PRTLDRMODINTERNAL pMod, void pvBits, RTUINTPTR BaseAddress, PFNRTLDRIMPORT pfnGetImport, void pvUser)
509	{
510	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
511
512	/*
513	* Load the bits into pvBits.
514	*/
515	const Elf_Shdr *paShdrs = pModElf->paShdrs;
516	for (unsigned iShdr = 0; iShdr < pModElf->Ehdr.e_shnum; iShdr++)
517	{
518	if (paShdrs[iShdr].sh_flags & SHF_ALLOC)
519	{
520	AssertMsgReturn((size_t)paShdrs[iShdr].sh_size == (size_t)paShdrs[iShdr].sh_size, (FMT_ELF_SIZE "\n", paShdrs[iShdr].sh_size), VERR_IMAGE_TOO_BIG);
521	switch (paShdrs[iShdr].sh_type)
522	{
523	case SHT_NOBITS:
524	memset((uint8_t *)pvBits + paShdrs[iShdr].sh_addr, 0, (size_t)paShdrs[iShdr].sh_size);
525	break;
526
527	case SHT_PROGBITS:
528	default:
529	{
530	int rc = pModElf->pReader->pfnRead(pModElf->pReader, (uint8_t *)pvBits + paShdrs[iShdr].sh_addr,
531	(size_t)paShdrs[iShdr].sh_size, paShdrs[iShdr].sh_offset);
532	if (RT_FAILURE(rc))
533	{
534	Log(("RTLdrELF: %s: Read error when reading " FMT_ELF_SIZE " bytes at " FMT_ELF_OFF ", iShdr=%d\n",
535	pModElf->pReader->pfnLogName(pModElf->pReader),
536	paShdrs[iShdr].sh_size, paShdrs[iShdr].sh_offset, iShdr));
537	return rc;
538	}
539	}
540	}
541	}
542	}
543
544	/*
545	* Relocate the image.
546	*/
547	return pModElf->Core.pOps->pfnRelocate(pMod, pvBits, BaseAddress, ~(RTUINTPTR)0, pfnGetImport, pvUser);
548	}
549
550
551	/** @copydoc RTLDROPS::Relocate */
552	static DECLCALLBACK(int) RTLDRELF_NAME(Relocate)(PRTLDRMODINTERNAL pMod, void pvBits, RTUINTPTR NewBaseAddress, RTUINTPTR OldBaseAddress, PFNRTLDRIMPORT pfnGetImport, void pvUser)
553	{
554	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
555
556	/*
557	* Validate the input.
558	*/
559	Elf_Addr BaseAddr = (Elf_Addr)NewBaseAddress;
560	AssertMsgReturn((RTUINTPTR)BaseAddr == NewBaseAddress, ("#RTptr", NewBaseAddress), VERR_IMAGE_BASE_TOO_HIGH);
561
562	/*
563	* Map the image bits if not already done and setup pointer into it.
564	*/
565	int rc = RTLDRELF_NAME(MapBits)(pModElf, true);
566	if (RT_FAILURE(rc))
567	return rc;
568
569	/*
570	* Iterate the sections looking for interesting SHT_REL[A] sections.
571	* SHT_REL[A] sections have the section index of the section they contain fixups
572	* for in the sh_info member.
573	*/
574	const Elf_Shdr *paShdrs = pModElf->paShdrs;
575	#ifdef LOG_ENABLED
576	const char *pszLogName = pModElf->pReader->pfnLogName(pModElf->pReader);
577	Log2(("rtLdrElf: %s: Fixing up image\n", pszLogName));
578	#endif
579	for (unsigned iShdr = 0; iShdr < pModElf->Ehdr.e_shnum; iShdr++)
580	{
581	const Elf_Shdr *pShdrRel = &paShdrs[iShdr];
582
583	/*
584	* Skip sections without interest to us.
585	*/
586	#if ELF_MODE == 32
587	if (pShdrRel->sh_type != SHT_REL)
588	#else
589	if (pShdrRel->sh_type != SHT_RELA)
590	#endif
591	continue;
592	if (pShdrRel->sh_info >= pModElf->Ehdr.e_shnum)
593	continue;
594	const Elf_Shdr pShdr = &paShdrs[pShdrRel->sh_info]; / the section to fixup. */
595	if (!(pShdr->sh_flags & SHF_ALLOC))
596	continue;
597
598	/*
599	* Relocate the section.
600	*/
601	Log2(("rtldrELF: %s: Relocation records for #%d [%s] (sh_info=%d sh_link=%d) found in #%d [%s] (sh_info=%d sh_link=%d)\n",
602	pszLogName, (int)pShdrRel->sh_info, ELF_STR(pModElf, pShdr->sh_name), (int)pShdr->sh_info, (int)pShdr->sh_link,
603	iShdr, ELF_STR(pModElf, pShdrRel->sh_name), (int)pShdrRel->sh_info, (int)pShdrRel->sh_link));
604
605	/** @todo Make RelocateSection a function pointer so we can select the one corresponding to the machine when opening the image. */
606	rc = RTLDRELF_NAME(RelocateSection)(pModElf, BaseAddr, pfnGetImport, pvUser,
607	pShdr->sh_addr,
608	pShdr->sh_size,
609	(const uint8_t *)pModElf->pvBits + pShdr->sh_offset,
610	(uint8_t *)pvBits + pShdr->sh_addr,
611	(const uint8_t *)pModElf->pvBits + pShdrRel->sh_offset,
612	pShdrRel->sh_size);
613	if (RT_FAILURE(rc))
614	return rc;
615	}
616	return VINF_SUCCESS;
617	}
618
619
620	/** @copydoc RTLDROPS::pfnGetSymbolEx */
621	static DECLCALLBACK(int) RTLDRELF_NAME(GetSymbolEx)(PRTLDRMODINTERNAL pMod, const void pvBits, RTUINTPTR BaseAddress, const char pszSymbol, RTUINTPTR *pValue)
622	{
623	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
624	NOREF(pvBits);
625
626	/*
627	* Validate the input.
628	*/
629	Elf_Addr BaseAddr = (Elf_Addr)BaseAddress;
630	AssertMsgReturn((RTUINTPTR)BaseAddr == BaseAddress, ("#RTptr", BaseAddress), VERR_IMAGE_BASE_TOO_HIGH);
631
632	/*
633	* Map the image bits if not already done and setup pointer into it.
634	*/
635	int rc = RTLDRELF_NAME(MapBits)(pModElf, true);
636	if (RT_FAILURE(rc))
637	return rc;
638
639	/*
640	* Calc all kinds of pointers before we start iterating the symbol table.
641	*/
642	const char *pStr = pModElf->pStr;
643	const Elf_Sym *paSyms = pModElf->paSyms;
644	unsigned cSyms = pModElf->cSyms;
645	for (unsigned iSym = 1; iSym < cSyms; iSym++)
646	{
647	/* Undefined symbols are not exports, they are imports. */
648	if ( paSyms[iSym].st_shndx != SHN_UNDEF
649	&& ( ELF_ST_BIND(paSyms[iSym].st_info) == STB_GLOBAL
650	\|\| ELF_ST_BIND(paSyms[iSym].st_info) == STB_WEAK))
651	{
652	/* Validate the name string and try match with it. */
653	if (paSyms[iSym].st_name < pModElf->cbStr)
654	{
655	if (!strcmp(pszSymbol, pStr + paSyms[iSym].st_name))
656	{
657	/* matched! */
658	Elf_Addr Value;
659	if (paSyms[iSym].st_shndx == SHN_ABS)
660	/* absolute symbols are not subject to any relocation. */
661	Value = paSyms[iSym].st_value;
662	else if (paSyms[iSym].st_shndx < pModElf->Ehdr.e_shnum)
663	/* relative to the section. */
664	Value = BaseAddr + paSyms[iSym].st_value + pModElf->paShdrs[paSyms[iSym].st_shndx].sh_addr;
665	else
666	{
667	AssertMsgFailed(("Arg. paSyms[iSym].st_shndx=%d\n", paSyms[iSym].st_shndx));
668	return VERR_BAD_EXE_FORMAT;
669	}
670	AssertMsgReturn(Value == (RTUINTPTR)Value, (FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG);
671	*pValue = (RTUINTPTR)Value;
672	return VINF_SUCCESS;
673	}
674	}
675	else
676	{
677	AssertMsgFailed(("String outside string table! iSym=%d paSyms[iSym].st_name=%#x\n", iSym, paSyms[iSym].st_name));
678	return VERR_LDRELF_INVALID_SYMBOL_NAME_OFFSET;
679	}
680	}
681	}
682
683	return VERR_SYMBOL_NOT_FOUND;
684	}
685
686
687	/** @copydoc RTLDROPS::pfnEnumDbgInfo */
688	static DECLCALLBACK(int) RTLDRELF_NAME(EnumDbgInfo)(PRTLDRMODINTERNAL pMod, const void *pvBits,
689	PFNRTLDRENUMDBG pfnCallback, void *pvUser)
690	{
691	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
692	NOREF(pvBits);
693
694	return VERR_NOT_IMPLEMENTED; NOREF(pModElf);
695	}
696
697
698	/** @copydoc RTLDROPS::pfnEnumSegments. */
699	static DECLCALLBACK(int) RTLDRELF_NAME(EnumSegments)(PRTLDRMODINTERNAL pMod, PFNRTLDRENUMSEGS pfnCallback, void *pvUser)
700	{
701	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
702
703	return VERR_NOT_IMPLEMENTED; NOREF(pModElf);
704	}
705
706
707	/** @copydoc RTLDROPS::pfnLinkAddressToSegOffset. */
708	static DECLCALLBACK(int) RTLDRELF_NAME(LinkAddressToSegOffset)(PRTLDRMODINTERNAL pMod, RTLDRADDR LinkAddress,
709	uint32_t *piSeg, PRTLDRADDR poffSeg)
710	{
711	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
712
713	return VERR_NOT_IMPLEMENTED; NOREF(pModElf);
714	}
715
716
717	/** @copydoc RTLDROPS::pfnLinkAddressToRva. */
718	static DECLCALLBACK(int) RTLDRELF_NAME(LinkAddressToRva)(PRTLDRMODINTERNAL pMod, RTLDRADDR LinkAddress, PRTLDRADDR pRva)
719	{
720	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
721
722	return VERR_NOT_IMPLEMENTED; NOREF(pModElf);
723	}
724
725
726	/** @copydoc RTLDROPS::pfnSegOffsetToRva. */
727	static DECLCALLBACK(int) RTLDRELF_NAME(SegOffsetToRva)(PRTLDRMODINTERNAL pMod, uint32_t iSeg, RTLDRADDR offSeg,
728	PRTLDRADDR pRva)
729	{
730	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
731
732	return VERR_NOT_IMPLEMENTED; NOREF(pModElf);
733	}
734
735
736	/** @copydoc RTLDROPS::pfnRvaToSegOffset. */
737	static DECLCALLBACK(int) RTLDRELF_NAME(RvaToSegOffset)(PRTLDRMODINTERNAL pMod, RTLDRADDR Rva,
738	uint32_t *piSeg, PRTLDRADDR poffSeg)
739	{
740	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
741
742	return VERR_NOT_IMPLEMENTED; NOREF(pModElf);
743	}
744
745
746
747	/**
748	* The ELF module operations.
749	*/
750	static RTLDROPS RTLDRELF_MID(s_rtldrElf,Ops) =
751	{
752	#if ELF_MODE == 32
753	"elf32",
754	#elif ELF_MODE == 64
755	"elf64",
756	#endif
757	RTLDRELF_NAME(Close),
758	NULL, /* Get Symbol */
759	RTLDRELF_NAME(Done),
760	RTLDRELF_NAME(EnumSymbols),
761	/* ext: */
762	RTLDRELF_NAME(GetImageSize),
763	RTLDRELF_NAME(GetBits),
764	RTLDRELF_NAME(Relocate),
765	RTLDRELF_NAME(GetSymbolEx),
766	RTLDRELF_NAME(EnumDbgInfo),
767	RTLDRELF_NAME(EnumSegments),
768	RTLDRELF_NAME(LinkAddressToSegOffset),
769	RTLDRELF_NAME(LinkAddressToRva),
770	RTLDRELF_NAME(SegOffsetToRva),
771	RTLDRELF_NAME(RvaToSegOffset),
772	42
773	};
774
775
776
777	/**
778	* Validates the ELF header.
779	*
780	* @returns iprt status code.
781	* @param pEhdr Pointer to the ELF header.
782	* @param pszLogName The log name.
783	* @param cbRawImage The size of the raw image.
784	*/
785	static int RTLDRELF_NAME(ValidateElfHeader)(const Elf_Ehdr pEhdr, const char pszLogName, uint64_t cbRawImage, PRTLDRARCH penmArch)
786	{
787	Log3(("RTLdrELF: e_ident: %.*Rhxs\n"
788	"RTLdrELF: e_type: " FMT_ELF_HALF "\n"
789	"RTLdrELF: e_version: " FMT_ELF_HALF "\n"
790	"RTLdrELF: e_entry: " FMT_ELF_ADDR "\n"
791	"RTLdrELF: e_phoff: " FMT_ELF_OFF "\n"
792	"RTLdrELF: e_shoff: " FMT_ELF_OFF "\n"
793	"RTLdrELF: e_flags: " FMT_ELF_WORD "\n"
794	"RTLdrELF: e_ehsize: " FMT_ELF_HALF "\n"
795	"RTLdrELF: e_phentsize: " FMT_ELF_HALF "\n"
796	"RTLdrELF: e_phnum: " FMT_ELF_HALF "\n"
797	"RTLdrELF: e_shentsize: " FMT_ELF_HALF "\n"
798	"RTLdrELF: e_shnum: " FMT_ELF_HALF "\n"
799	"RTLdrELF: e_shstrndx: " FMT_ELF_HALF "\n",
800	RT_ELEMENTS(pEhdr->e_ident), &pEhdr->e_ident[0], pEhdr->e_type, pEhdr->e_version,
801	pEhdr->e_entry, pEhdr->e_phoff, pEhdr->e_shoff,pEhdr->e_flags, pEhdr->e_ehsize, pEhdr->e_phentsize,
802	pEhdr->e_phnum, pEhdr->e_shentsize, pEhdr->e_shnum, pEhdr->e_shstrndx));
803
804	if ( pEhdr->e_ident[EI_MAG0] != ELFMAG0
805	\|\| pEhdr->e_ident[EI_MAG1] != ELFMAG1
806	\|\| pEhdr->e_ident[EI_MAG2] != ELFMAG2
807	\|\| pEhdr->e_ident[EI_MAG3] != ELFMAG3
808	)
809	{
810	Log(("RTLdrELF: %s: Invalid ELF magic (%.*Rhxs)\n", pszLogName, sizeof(pEhdr->e_ident), pEhdr->e_ident));
811	return VERR_BAD_EXE_FORMAT;
812	}
813	if (pEhdr->e_ident[EI_CLASS] != RTLDRELF_SUFF(ELFCLASS))
814	{
815	Log(("RTLdrELF: %s: Invalid ELF class (%.*Rhxs)\n", pszLogName, sizeof(pEhdr->e_ident), pEhdr->e_ident));
816	return VERR_BAD_EXE_FORMAT;
817	}
818	if (pEhdr->e_ident[EI_DATA] != ELFDATA2LSB)
819	{
820	Log(("RTLdrELF: %s: ELF endian %x is unsupported\n", pEhdr->e_ident[EI_DATA]));
821	return VERR_LDRELF_ODD_ENDIAN;
822	}
823	if (pEhdr->e_version != EV_CURRENT)
824	{
825	Log(("RTLdrELF: %s: ELF version %x is unsupported\n", pEhdr->e_version));
826	return VERR_LDRELF_VERSION;
827	}
828
829	if (sizeof(Elf_Ehdr) != pEhdr->e_ehsize)
830	{
831	Log(("RTLdrELF: %s: Elf header e_ehsize is %d expected %d!\n",
832	pszLogName, pEhdr->e_ehsize, sizeof(Elf_Ehdr)));
833	return VERR_BAD_EXE_FORMAT;
834	}
835	if ( sizeof(Elf_Phdr) != pEhdr->e_phentsize
836	&& ( pEhdr->e_phnum != 0
837	\|\| pEhdr->e_type == ET_DYN))
838	{
839	Log(("RTLdrELF: %s: Elf header e_phentsize is %d expected %d!\n",
840	pszLogName, pEhdr->e_phentsize, sizeof(Elf_Phdr)));
841	return VERR_BAD_EXE_FORMAT;
842	}
843	if (sizeof(Elf_Shdr) != pEhdr->e_shentsize)
844	{
845	Log(("RTLdrELF: %s: Elf header e_shentsize is %d expected %d!\n",
846	pszLogName, pEhdr->e_shentsize, sizeof(Elf_Shdr)));
847	return VERR_BAD_EXE_FORMAT;
848	}
849
850	switch (pEhdr->e_type)
851	{
852	case ET_REL:
853	break;
854	case ET_EXEC:
855	Log(("RTLdrELF: %s: Executable images are not supported yet!\n", pszLogName));
856	return VERR_LDRELF_EXEC;
857	case ET_DYN:
858	Log(("RTLdrELF: %s: Dynamic images are not supported yet!\n", pszLogName));
859	return VERR_LDRELF_DYN;
860	default:
861	Log(("RTLdrELF: %s: image type %#x is not supported!\n", pszLogName, pEhdr->e_type));
862	return VERR_BAD_EXE_FORMAT;
863	}
864
865	switch (pEhdr->e_machine)
866	{
867	#if ELF_MODE == 32
868	case EM_386:
869	case EM_486:
870	*penmArch = RTLDRARCH_X86_32;
871	break;
872	#elif ELF_MODE == 64
873	case EM_X86_64:
874	*penmArch = RTLDRARCH_AMD64;
875	break;
876	#endif
877	default:
878	Log(("RTLdrELF: %s: machine type %u is not supported!\n", pEhdr->e_machine));
879	return VERR_LDRELF_MACHINE;
880	}
881
882	if ( pEhdr->e_phoff < pEhdr->e_ehsize
883	&& !(pEhdr->e_phoff && pEhdr->e_phnum)
884	&& pEhdr->e_phnum)
885	{
886	Log(("RTLdrELF: %s: The program headers overlap with the ELF header! e_phoff=" FMT_ELF_OFF "\n",
887	pszLogName, pEhdr->e_phoff));
888	return VERR_BAD_EXE_FORMAT;
889	}
890	if ( pEhdr->e_phoff + pEhdr->e_phnum * pEhdr->e_phentsize > cbRawImage
891	\|\| pEhdr->e_phoff + pEhdr->e_phnum * pEhdr->e_phentsize < pEhdr->e_phoff)
892	{
893	Log(("RTLdrELF: %s: The program headers extends beyond the file! e_phoff=" FMT_ELF_OFF " e_phnum=" FMT_ELF_HALF "\n",
894	pszLogName, pEhdr->e_phoff, pEhdr->e_phnum));
895	return VERR_BAD_EXE_FORMAT;
896	}
897
898
899	if ( pEhdr->e_shoff < pEhdr->e_ehsize
900	&& !(pEhdr->e_shoff && pEhdr->e_shnum))
901	{
902	Log(("RTLdrELF: %s: The section headers overlap with the ELF header! e_shoff=" FMT_ELF_OFF "\n",
903	pszLogName, pEhdr->e_shoff));
904	return VERR_BAD_EXE_FORMAT;
905	}
906	if ( pEhdr->e_shoff + pEhdr->e_shnum * pEhdr->e_shentsize > cbRawImage
907	\|\| pEhdr->e_shoff + pEhdr->e_shnum * pEhdr->e_shentsize < pEhdr->e_shoff)
908	{
909	Log(("RTLdrELF: %s: The section headers extends beyond the file! e_shoff=" FMT_ELF_OFF " e_shnum=" FMT_ELF_HALF "\n",
910	pszLogName, pEhdr->e_shoff, pEhdr->e_shnum));
911	return VERR_BAD_EXE_FORMAT;
912	}
913
914	return VINF_SUCCESS;
915	}
916
917	/**
918	* Gets the section header name.
919	*
920	* @returns pszName.
921	* @param pReader The loader reader instance.
922	* @param pEhdr The elf header.
923	* @param offName The offset of the section header name.
924	* @param pszName Where to store the name.
925	* @param cbName The size of the buffer pointed to by pszName.
926	*/
927	const char RTLDRELF_NAME(GetSHdrName)(PRTLDRMODELF pModElf, Elf_Word offName, char pszName, size_t cbName)
928	{
929	RTFOFF off = pModElf->paShdrs[pModElf->Ehdr.e_shstrndx].sh_offset + offName;
930	int rc = pModElf->pReader->pfnRead(pModElf->pReader, pszName, cbName - 1, off);
931	if (RT_FAILURE(rc))
932	{
933	/* read by for byte. */
934	for (unsigned i = 0; i < cbName; i++, off++)
935	{
936	rc = pModElf->pReader->pfnRead(pModElf->pReader, pszName + i, 1, off);
937	if (RT_FAILURE(rc))
938	{
939	pszName[i] = '\0';
940	break;
941	}
942	}
943	}
944
945	pszName[cbName - 1] = '\0';
946	return pszName;
947	}
948
949
950	/**
951	* Validates a section header.
952	*
953	* @returns iprt status code.
954	* @param pModElf Pointer to the module structure.
955	* @param iShdr The index of section header which should be validated.
956	* The section headers are found in the pModElf->paShdrs array.
957	* @param pszLogName The log name.
958	* @param cbRawImage The size of the raw image.
959	*/
960	static int RTLDRELF_NAME(ValidateSectionHeader)(PRTLDRMODELF pModElf, unsigned iShdr, const char *pszLogName, RTFOFF cbRawImage)
961	{
962	const Elf_Shdr *pShdr = &pModElf->paShdrs[iShdr];
963	char szSectionName[80]; NOREF(szSectionName);
964	Log3(("RTLdrELF: Section Header #%d:\n"
965	"RTLdrELF: sh_name: " FMT_ELF_WORD " - %s\n"
966	"RTLdrELF: sh_type: " FMT_ELF_WORD " (%s)\n"
967	"RTLdrELF: sh_flags: " FMT_ELF_XWORD "\n"
968	"RTLdrELF: sh_addr: " FMT_ELF_ADDR "\n"
969	"RTLdrELF: sh_offset: " FMT_ELF_OFF "\n"
970	"RTLdrELF: sh_size: " FMT_ELF_XWORD "\n"
971	"RTLdrELF: sh_link: " FMT_ELF_WORD "\n"
972	"RTLdrELF: sh_info: " FMT_ELF_WORD "\n"
973	"RTLdrELF: sh_addralign: " FMT_ELF_XWORD "\n"
974	"RTLdrELF: sh_entsize: " FMT_ELF_XWORD "\n",
975	iShdr,
976	pShdr->sh_name, RTLDRELF_NAME(GetSHdrName)(pModElf, pShdr->sh_name, szSectionName, sizeof(szSectionName)),
977	pShdr->sh_type, rtldrElfGetShdrType(pShdr->sh_type), pShdr->sh_flags, pShdr->sh_addr,
978	pShdr->sh_offset, pShdr->sh_size, pShdr->sh_link, pShdr->sh_info, pShdr->sh_addralign,
979	pShdr->sh_entsize));
980
981	if (pShdr->sh_link >= pModElf->Ehdr.e_shnum)
982	{
983	Log(("RTLdrELF: %s: Shdr #%d: sh_link (%d) is beyond the end of the section table (%d)!\n",
984	pszLogName, iShdr, pShdr->sh_link, pModElf->Ehdr.e_shnum));
985	return VERR_BAD_EXE_FORMAT;
986	}
987
988	switch (pShdr->sh_type)
989	{
990	/** @todo find specs and check up which sh_info fields indicates section table entries */
991	case 12301230:
992	if (pShdr->sh_info >= pModElf->Ehdr.e_shnum)
993	{
994	Log(("RTLdrELF: %s: Shdr #%d: sh_info (%d) is beyond the end of the section table (%d)!\n",
995	pszLogName, iShdr, pShdr->sh_link, pModElf->Ehdr.e_shnum));
996	return VERR_BAD_EXE_FORMAT;
997	}
998	break;
999
1000	case SHT_NULL:
1001	case SHT_PROGBITS:
1002	case SHT_SYMTAB:
1003	case SHT_STRTAB:
1004	case SHT_RELA:
1005	case SHT_HASH:
1006	case SHT_DYNAMIC:
1007	case SHT_NOTE:
1008	case SHT_NOBITS:
1009	case SHT_REL:
1010	case SHT_SHLIB:
1011	case SHT_DYNSYM:
1012	/*
1013	* For these types sh_info doesn't have any special meaning, or anything which
1014	* we need/can validate now.
1015	*/
1016	break;
1017
1018
1019	default:
1020	Log(("RTLdrELF: %s: Warning, unknown type %d!\n", pszLogName, pShdr->sh_type));
1021	break;
1022	}
1023
1024	if ( pShdr->sh_type != SHT_NOBITS
1025	&& pShdr->sh_size)
1026	{
1027	RTFOFF offEnd = pShdr->sh_offset + pShdr->sh_size;
1028	if ( offEnd > cbRawImage
1029	\|\| offEnd < (RTFOFF)pShdr->sh_offset)
1030	{
1031	Log(("RTLdrELF: %s: Shdr #%d: sh_offset (" FMT_ELF_OFF ") + sh_size (" FMT_ELF_XWORD " = %RTfoff) is beyond the end of the file (%RTfoff)!\n",
1032	pszLogName, iShdr, pShdr->sh_offset, pShdr->sh_size, offEnd, cbRawImage));
1033	return VERR_BAD_EXE_FORMAT;
1034	}
1035	if (pShdr->sh_offset < sizeof(Elf_Ehdr))
1036	{
1037	Log(("RTLdrELF: %s: Shdr #%d: sh_offset (" FMT_ELF_OFF ") + sh_size (" FMT_ELF_XWORD ") is starting in the ELF header!\n",
1038	pszLogName, iShdr, pShdr->sh_offset, pShdr->sh_size, cbRawImage));
1039	return VERR_BAD_EXE_FORMAT;
1040	}
1041	}
1042
1043	return VINF_SUCCESS;
1044	}
1045
1046
1047
1048	/**
1049	* Opens an ELF image, fixed bitness.
1050	*
1051	* @returns iprt status code.
1052	* @param pReader The loader reader instance which will provide the raw image bits.
1053	* @param fFlags Reserved, MBZ.
1054	* @param enmArch Architecture specifier.
1055	* @param phLdrMod Where to store the handle.
1056	*/
1057	static int RTLDRELF_NAME(Open)(PRTLDRREADER pReader, uint32_t fFlags, RTLDRARCH enmArch, PRTLDRMOD phLdrMod)
1058	{
1059	const char *pszLogName = pReader->pfnLogName(pReader);
1060	RTFOFF cbRawImage = pReader->pfnSize(pReader);
1061
1062	/*
1063	* Create the loader module instance.
1064	*/
1065	PRTLDRMODELF pModElf = (PRTLDRMODELF)RTMemAllocZ(sizeof(*pModElf));
1066	if (!pModElf)
1067	return VERR_NO_MEMORY;
1068
1069	pModElf->Core.u32Magic = RTLDRMOD_MAGIC;
1070	pModElf->Core.eState = LDR_STATE_INVALID;
1071	pModElf->pReader = pReader;
1072	//pModElf->pvBits = NULL;
1073	//pModElf->Ehdr = {0};
1074	//pModElf->paShdrs = NULL;
1075	//pModElf->paSyms = NULL;
1076	pModElf->iSymSh = ~0U;
1077	pModElf->cSyms = 0;
1078	pModElf->iStrSh = ~0U;
1079	pModElf->cbStr = 0;
1080	pModElf->cbImage = 0;
1081	//pModElf->pStr = NULL;
1082
1083	/*
1084	* Read and validate the ELF header and match up the CPU architecture.
1085	*/
1086	int rc = pReader->pfnRead(pReader, &pModElf->Ehdr, sizeof(pModElf->Ehdr), 0);
1087	if (RT_SUCCESS(rc))
1088	{
1089	RTLDRARCH enmArchImage = RTLDRARCH_INVALID; /* shut up gcc */
1090	rc = RTLDRELF_NAME(ValidateElfHeader)(&pModElf->Ehdr, pszLogName, cbRawImage, &enmArchImage);
1091	if (RT_SUCCESS(rc))
1092	{
1093	if ( enmArch != RTLDRARCH_WHATEVER
1094	&& enmArch != enmArchImage)
1095	rc = VERR_LDR_ARCH_MISMATCH;
1096	}
1097	}
1098	if (RT_SUCCESS(rc))
1099	{
1100	/*
1101	* Read the section headers.
1102	*/
1103	Elf_Shdr paShdrs = (Elf_Shdr )RTMemAlloc(pModElf->Ehdr.e_shnum * sizeof(Elf_Shdr));
1104	if (paShdrs)
1105	{
1106	pModElf->paShdrs = paShdrs;
1107	rc = pReader->pfnRead(pReader, paShdrs, pModElf->Ehdr.e_shnum * sizeof(Elf_Shdr),
1108	pModElf->Ehdr.e_shoff);
1109	if (RT_SUCCESS(rc))
1110	{
1111	/*
1112	* Validate the section headers, allocate memory for the sections (determine the image size),
1113	* and find relevant sections.
1114	*/
1115	for (unsigned i = 0; i < pModElf->Ehdr.e_shnum; i++)
1116	{
1117	rc = RTLDRELF_NAME(ValidateSectionHeader)(pModElf, i, pszLogName, cbRawImage);
1118	if (RT_FAILURE(rc))
1119	break;
1120
1121	/* Allocate memory addresses for the section. */
1122	if (paShdrs[i].sh_flags & SHF_ALLOC)
1123	{
1124	paShdrs[i].sh_addr = paShdrs[i].sh_addralign
1125	? RT_ALIGN_T(pModElf->cbImage, paShdrs[i].sh_addralign, Elf_Addr)
1126	: (Elf_Addr)pModElf->cbImage;
1127	pModElf->cbImage = (size_t)paShdrs[i].sh_addr + (size_t)paShdrs[i].sh_size;
1128	AssertMsgReturn(pModElf->cbImage == paShdrs[i].sh_addr + paShdrs[i].sh_size,
1129	(FMT_ELF_ADDR "\n", paShdrs[i].sh_addr + paShdrs[i].sh_size),
1130	VERR_IMAGE_TOO_BIG);
1131	Log2(("RTLdrElf: %s: Assigned " FMT_ELF_ADDR " to section #%d\n", pszLogName, paShdrs[i].sh_addr, i));
1132	}
1133
1134	/* We're looking for symbol tables. */
1135	if (paShdrs[i].sh_type == SHT_SYMTAB)
1136	{
1137	if (pModElf->iSymSh != ~0U)
1138	{
1139	Log(("RTLdrElf: %s: Multiple symbol tabs! iSymSh=%d i=%d\n", pszLogName, pModElf->iSymSh, i));
1140	rc = VERR_LDRELF_MULTIPLE_SYMTABS;
1141	break;
1142	}
1143	pModElf->iSymSh = i;
1144	pModElf->cSyms = (unsigned)(paShdrs[i].sh_size / sizeof(Elf_Sym));
1145	AssertReturn(pModElf->cSyms == paShdrs[i].sh_size / sizeof(Elf_Sym), VERR_IMAGE_TOO_BIG);
1146	pModElf->iStrSh = paShdrs[i].sh_link;
1147	pModElf->cbStr = (unsigned)paShdrs[pModElf->iStrSh].sh_size;
1148	AssertReturn(pModElf->cbStr == paShdrs[pModElf->iStrSh].sh_size, VERR_IMAGE_TOO_BIG);
1149	}
1150	} /* for each section header */
1151
1152	Log2(("RTLdrElf: iSymSh=%u cSyms=%u iStrSh=%u cbStr=%u rc=%Rrc cbImage=%#zx\n",
1153	pModElf->iSymSh, pModElf->cSyms, pModElf->iStrSh, pModElf->cbStr, rc, pModElf->cbImage));
1154
1155	/*
1156	* Are the section headers fine?
1157	* We require there to be symbol & string tables (at least for the time being).
1158	*/
1159	if ( pModElf->iSymSh == ~0U
1160	\|\| pModElf->iStrSh == ~0U)
1161	rc = VERR_LDRELF_NO_SYMBOL_OR_NO_STRING_TABS;
1162	if (RT_SUCCESS(rc))
1163	{
1164	pModElf->Core.pOps = &RTLDRELF_MID(s_rtldrElf,Ops);
1165	pModElf->Core.eState = LDR_STATE_OPENED;
1166	*phLdrMod = &pModElf->Core;
1167
1168	LogFlow(("%s: %s: returns VINF_SUCCESS phLdrMod=%p\n", __FUNCTION__, pszLogName, phLdrMod));
1169	return VINF_SUCCESS;
1170	}
1171	}
1172
1173	RTMemFree(paShdrs);
1174	}
1175	else
1176	rc = VERR_NO_MEMORY;
1177	}
1178
1179	RTMemFree(pModElf);
1180	LogFlow(("%s: returns %Rrc\n", __FUNCTION__, rc));
1181	return rc;
1182	}
1183
1184
1185
1186
1187	/*******************************************************************************
1188	* Cleanup Constants And Macros *
1189	*******************************************************************************/
1190	#undef RTLDRELF_NAME
1191	#undef RTLDRELF_SUFF
1192	#undef RTLDRELF_MID
1193
1194	#undef FMT_ELF_ADDR
1195	#undef FMT_ELF_HALF
1196	#undef FMT_ELF_SHALF
1197	#undef FMT_ELF_OFF
1198	#undef FMT_ELF_SIZE
1199	#undef FMT_ELF_SWORD
1200	#undef FMT_ELF_WORD
1201	#undef FMT_ELF_XWORD
1202	#undef FMT_ELF_SXWORD
1203
1204	#undef Elf_Ehdr
1205	#undef Elf_Phdr
1206	#undef Elf_Shdr
1207	#undef Elf_Sym
1208	#undef Elf_Rel
1209	#undef Elf_Rela
1210	#undef Elf_Reloc
1211	#undef Elf_Nhdr
1212	#undef Elf_Dyn
1213
1214	#undef Elf_Addr
1215	#undef Elf_Half
1216	#undef Elf_Off
1217	#undef Elf_Size
1218	#undef Elf_Sword
1219	#undef Elf_Word
1220
1221	#undef RTLDRMODELF
1222	#undef PRTLDRMODELF
1223
1224	#undef ELF_R_SYM
1225	#undef ELF_R_TYPE
1226	#undef ELF_R_INFO
1227
1228	#undef ELF_ST_BIND
1229

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

source: vbox/trunk/src/VBox/Runtime/common/ldr/ldrELFRelocatable.cpp.h@ 39070

Download in other formats: