ldrELFRelocatable.cpp.h@ 42599

Last change on this file since 42599 was 41510, checked in by vboxsync, 13 years ago
IPRT/Elf: Working on loading watcom dwarf symbol files.
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1	/* $Id: ldrELFRelocatable.cpp.h 41510 2012-05-30 20:05:54Z 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	if (pModElf->iSymSh != ~0U)
144	pModElf->paSyms = (const Elf_Sym *)(pu8 + pModElf->paShdrs[pModElf->iSymSh].sh_offset);
145	if (pModElf->iStrSh != ~0U)
146	pModElf->pStr = (const char *)(pu8 + pModElf->paShdrs[pModElf->iStrSh].sh_offset);
147	}
148	return rc;
149	}
150
151
152	/**
153	* Get the symbol and symbol value.
154	*
155	* @returns iprt status code.
156	* @param pModElf The ELF loader module instance data.
157	* @param BaseAddr The base address which the module is being fixedup to.
158	* @param pfnGetImport The callback function to use to resolve imports (aka unresolved externals).
159	* @param pvUser User argument to pass to the callback.
160	* @param iSym The symbol to get.
161	* @param ppSym Where to store the symbol pointer on success. (read only)
162	* @param pSymValue Where to store the symbol value on success.
163	*/
164	static int RTLDRELF_NAME(Symbol)(PRTLDRMODELF pModElf, Elf_Addr BaseAddr, PFNRTLDRIMPORT pfnGetImport, void *pvUser,
165	Elf_Size iSym, const Elf_Sym *ppSym, Elf_Addr pSymValue)
166	{
167	/*
168	* Validate and find the symbol.
169	*/
170	if (iSym >= pModElf->cSyms)
171	{
172	AssertMsgFailed(("iSym=%d is an invalid symbol index!\n", iSym));
173	return VERR_LDRELF_INVALID_SYMBOL_INDEX;
174	}
175	const Elf_Sym *pSym = &pModElf->paSyms[iSym];
176	*ppSym = pSym;
177
178	if (pSym->st_name >= pModElf->cbStr)
179	{
180	AssertMsgFailed(("iSym=%d st_name=%d str sh_size=%d\n", iSym, pSym->st_name, pModElf->cbStr));
181	return VERR_LDRELF_INVALID_SYMBOL_NAME_OFFSET;
182	}
183	const char *pszName = ELF_STR(pModElf, pSym->st_name);
184
185	/*
186	* Determine the symbol value.
187	*
188	* Symbols needs different treatment depending on which section their are in.
189	* Undefined and absolute symbols goes into special non-existing sections.
190	*/
191	switch (pSym->st_shndx)
192	{
193	/*
194	* Undefined symbol, needs resolving.
195	*
196	* Since ELF has no generic concept of importing from specific module (the OS/2 ELF format
197	* has but that's a OS extension and only applies to programs and dlls), we'll have to ask
198	* the resolver callback to do a global search.
199	*/
200	case SHN_UNDEF:
201	{
202	/* Try to resolve the symbol. */
203	RTUINTPTR Value;
204	int rc = pfnGetImport(&pModElf->Core, "", pszName, ~0, &Value, pvUser);
205	if (RT_FAILURE(rc))
206	{
207	AssertMsgFailed(("Failed to resolve '%s' rc=%Rrc\n", pszName, rc));
208	return rc;
209	}
210	*pSymValue = (Elf_Addr)Value;
211	if ((RTUINTPTR)*pSymValue != Value)
212	{
213	AssertMsgFailed(("Symbol value overflowed! '%s'\n", pszName));
214	return VERR_SYMBOL_VALUE_TOO_BIG;
215	}
216
217	Log2(("rtldrELF: #%-3d - UNDEF " FMT_ELF_ADDR " '%s'\n", iSym, *pSymValue, pszName));
218	break;
219	}
220
221	/*
222	* Absolute symbols needs no fixing since they are, well, absolute.
223	*/
224	case SHN_ABS:
225	*pSymValue = pSym->st_value;
226	Log2(("rtldrELF: #%-3d - ABS " FMT_ELF_ADDR " '%s'\n", iSym, *pSymValue, pszName));
227	break;
228
229	/*
230	* All other symbols are addressed relative to their section and need to be fixed up.
231	*/
232	default:
233	if (pSym->st_shndx >= pModElf->Ehdr.e_shnum)
234	{
235	/* what about common symbols? */
236	AssertMsg(pSym->st_shndx < pModElf->Ehdr.e_shnum,
237	("iSym=%d st_shndx=%d e_shnum=%d pszName=%s\n", iSym, pSym->st_shndx, pModElf->Ehdr.e_shnum, pszName));
238	return VERR_BAD_EXE_FORMAT;
239	}
240	*pSymValue = pSym->st_value + pModElf->paShdrs[pSym->st_shndx].sh_addr + BaseAddr;
241	Log2(("rtldrELF: #%-3d - %5d " FMT_ELF_ADDR " '%s'\n", iSym, pSym->st_shndx, *pSymValue, pszName));
242	break;
243	}
244
245	return VINF_SUCCESS;
246	}
247
248
249	/**
250	* Applies the fixups for a sections.
251	*
252	* @returns iprt status code.
253	* @param pModElf The ELF loader module instance data.
254	* @param BaseAddr The base address which the module is being fixedup to.
255	* @param pfnGetImport The callback function to use to resolve imports (aka unresolved externals).
256	* @param pvUser User argument to pass to the callback.
257	* @param SecAddr The section address. This is the address the relocations are relative to.
258	* @param cbSec The section size. The relocations must be inside this.
259	* @param pu8SecBaseR Where we read section bits from.
260	* @param pu8SecBaseW Where we write section bits to.
261	* @param pvRelocs Pointer to where we read the relocations from.
262	* @param cbRelocs Size of the relocations.
263	*/
264	static int RTLDRELF_NAME(RelocateSection)(PRTLDRMODELF pModElf, Elf_Addr BaseAddr, PFNRTLDRIMPORT pfnGetImport, void *pvUser,
265	const Elf_Addr SecAddr, Elf_Size cbSec, const uint8_t pu8SecBaseR, uint8_t pu8SecBaseW,
266	const void *pvRelocs, Elf_Size cbRelocs)
267	{
268	#if ELF_MODE != 32
269	NOREF(pu8SecBaseR);
270	#endif
271
272	/*
273	* Iterate the relocations.
274	* The relocations are stored in an array of Elf32_Rel records and covers the entire relocation section.
275	*/
276	const Elf_Reloc paRels = (const Elf_Reloc )pvRelocs;
277	const unsigned iRelMax = (unsigned)(cbRelocs / sizeof(paRels[0]));
278	AssertMsgReturn(iRelMax == cbRelocs / sizeof(paRels[0]), (FMT_ELF_SIZE "\n", cbRelocs / sizeof(paRels[0])), VERR_IMAGE_TOO_BIG);
279	for (unsigned iRel = 0; iRel < iRelMax; iRel++)
280	{
281	/*
282	* Get the symbol.
283	*/
284	const Elf_Sym *pSym;
285	Elf_Addr SymValue = 0; /* shut up gcc-4 */
286	int rc = RTLDRELF_NAME(Symbol)(pModElf, BaseAddr, pfnGetImport, pvUser, ELF_R_SYM(paRels[iRel].r_info), &pSym, &SymValue);
287	if (RT_FAILURE(rc))
288	return rc;
289
290	Log3(("rtldrELF: " FMT_ELF_ADDR " %02x %06x - " FMT_ELF_ADDR " %3d %02x %s\n",
291	paRels[iRel].r_offset, ELF_R_TYPE(paRels[iRel].r_info), (unsigned)ELF_R_SYM(paRels[iRel].r_info),
292	SymValue, (unsigned)pSym->st_shndx, pSym->st_info, ELF_STR(pModElf, pSym->st_name)));
293
294	/*
295	* Apply the fixup.
296	*/
297	AssertMsgReturn(paRels[iRel].r_offset < cbSec, (FMT_ELF_ADDR " " FMT_ELF_SIZE "\n", paRels[iRel].r_offset, cbSec), VERR_LDRELF_INVALID_RELOCATION_OFFSET);
298	#if ELF_MODE == 32
299	const Elf_Addr pAddrR = (const Elf_Addr )(pu8SecBaseR + paRels[iRel].r_offset); /* Where to read the addend. */
300	#endif
301	Elf_Addr pAddrW = (Elf_Addr )(pu8SecBaseW + paRels[iRel].r_offset); /* Where to write the fixup. */
302	switch (ELF_R_TYPE(paRels[iRel].r_info))
303	{
304	#if ELF_MODE == 32
305	/*
306	* Absolute addressing.
307	*/
308	case R_386_32:
309	{
310	const Elf_Addr Value = SymValue + *pAddrR;
311	(uint32_t )pAddrW = Value;
312	Log4((FMT_ELF_ADDR": R_386_32 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n",
313	SecAddr + paRels[iRel].r_offset + BaseAddr, Value, SymValue));
314	break;
315	}
316
317	/*
318	* PC relative addressing.
319	*/
320	case R_386_PC32:
321	{
322	const Elf_Addr SourceAddr = SecAddr + paRels[iRel].r_offset + BaseAddr; /* Where the source really is. */
323	const Elf_Addr Value = SymValue + (uint32_t )pAddrR - SourceAddr;
324	(uint32_t )pAddrW = Value;
325	Log4((FMT_ELF_ADDR": R_386_PC32 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n",
326	SourceAddr, Value, SymValue));
327	break;
328	}
329
330	/* ignore */
331	case R_386_NONE:
332	break;
333
334	#elif ELF_MODE == 64
335
336	/*
337	* Absolute addressing
338	*/
339	case R_X86_64_64:
340	{
341	const Elf_Addr Value = SymValue + paRels[iRel].r_addend;
342	(uint64_t )pAddrW = Value;
343	Log4((FMT_ELF_ADDR": R_X86_64_64 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n",
344	SecAddr + paRels[iRel].r_offset + BaseAddr, Value, SymValue));
345	break;
346	}
347
348	/*
349	* Truncated 32-bit value (zero-extendedable to the 64-bit value).
350	*/
351	case R_X86_64_32:
352	{
353	const Elf_Addr Value = SymValue + paRels[iRel].r_addend;
354	(uint32_t )pAddrW = (uint32_t)Value;
355	Log4((FMT_ELF_ADDR": R_X86_64_32 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n",
356	SecAddr + paRels[iRel].r_offset + BaseAddr, Value, SymValue));
357	AssertMsgReturn((Elf_Addr)(uint32_t )pAddrW == Value, ("Value=" FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG);
358	break;
359	}
360
361	/*
362	* Truncated 32-bit value (sign-extendedable to the 64-bit value).
363	*/
364	case R_X86_64_32S:
365	{
366	const Elf_Addr Value = SymValue + paRels[iRel].r_addend;
367	(int32_t )pAddrW = (int32_t)Value;
368	Log4((FMT_ELF_ADDR": R_X86_64_32S Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n",
369	SecAddr + paRels[iRel].r_offset + BaseAddr, Value, SymValue));
370	AssertMsgReturn((Elf_Addr)(int32_t )pAddrW == Value, ("Value=" FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG); /** @todo check the sign-extending here. */
371	break;
372	}
373
374	/*
375	* PC relative addressing.
376	*/
377	case R_X86_64_PC32:
378	{
379	const Elf_Addr SourceAddr = SecAddr + paRels[iRel].r_offset + BaseAddr; /* Where the source really is. */
380	const Elf_Addr Value = SymValue + paRels[iRel].r_addend - SourceAddr;
381	(int32_t )pAddrW = (int32_t)Value;
382	Log4((FMT_ELF_ADDR": R_X86_64_PC32 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n",
383	SourceAddr, Value, SymValue));
384	AssertMsgReturn((Elf_Addr)(int32_t )pAddrW == Value, ("Value=" FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG); /** @todo check the sign-extending here. */
385	break;
386	}
387
388	/* ignore */
389	case R_X86_64_NONE:
390	break;
391	#endif
392
393	default:
394	AssertMsgFailed(("Unknown relocation type: %d (iRel=%d iRelMax=%d)\n",
395	ELF_R_TYPE(paRels[iRel].r_info), iRel, iRelMax));
396	return VERR_LDRELF_RELOCATION_NOT_SUPPORTED;
397	}
398	}
399
400	return VINF_SUCCESS;
401	}
402
403
404
405	/** @copydoc RTLDROPS::pfnClose */
406	static DECLCALLBACK(int) RTLDRELF_NAME(Close)(PRTLDRMODINTERNAL pMod)
407	{
408	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
409
410	if (pModElf->paShdrs)
411	{
412	RTMemFree(pModElf->paShdrs);
413	pModElf->paShdrs = NULL;
414	}
415
416	if (pModElf->pReader)
417	{
418	pModElf->pReader->pfnDestroy(pModElf->pReader);
419	pModElf->pReader = NULL;
420	}
421
422	pModElf->pvBits = NULL;
423
424	return VINF_SUCCESS;
425	}
426
427
428	/** @copydoc RTLDROPS::Done */
429	static DECLCALLBACK(int) RTLDRELF_NAME(Done)(PRTLDRMODINTERNAL pMod)
430	{
431	NOREF(pMod); /PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;/
432	/** @todo Have to think more about this .... */
433	return -1;
434	}
435
436
437	/** @copydoc RTLDROPS::EnumSymbols */
438	static DECLCALLBACK(int) RTLDRELF_NAME(EnumSymbols)(PRTLDRMODINTERNAL pMod, unsigned fFlags, const void *pvBits, RTUINTPTR BaseAddress,
439	PFNRTLDRENUMSYMS pfnCallback, void *pvUser)
440	{
441	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
442	NOREF(pvBits);
443
444	/*
445	* Validate the input.
446	*/
447	Elf_Addr BaseAddr = (Elf_Addr)BaseAddress;
448	AssertMsgReturn((RTUINTPTR)BaseAddr == BaseAddress, ("#RTptr", BaseAddress), VERR_IMAGE_BASE_TOO_HIGH);
449
450	/*
451	* Make sure we've got the string and symbol tables. (We don't need the pvBits.)
452	*/
453	int rc = RTLDRELF_NAME(MapBits)(pModElf, false);
454	if (RT_FAILURE(rc))
455	return rc;
456
457	/*
458	* Enumerate the symbol table.
459	*/
460	const Elf_Sym *paSyms = pModElf->paSyms;
461	unsigned cSyms = pModElf->cSyms;
462	for (unsigned iSym = 1; iSym < cSyms; iSym++)
463	{
464	/*
465	* Skip imports (undefined).
466	*/
467	if (paSyms[iSym].st_shndx != SHN_UNDEF)
468	{
469	/*
470	* Calc value and get name.
471	*/
472	Elf_Addr Value;
473	if (paSyms[iSym].st_shndx == SHN_ABS)
474	/* absolute symbols are not subject to any relocation. */
475	Value = paSyms[iSym].st_value;
476	else if (paSyms[iSym].st_shndx < pModElf->Ehdr.e_shnum)
477	/* relative to the section. */
478	Value = BaseAddr + paSyms[iSym].st_value + pModElf->paShdrs[paSyms[iSym].st_shndx].sh_addr;
479	else
480	{
481	AssertMsgFailed(("Arg! paSyms[%u].st_shndx=" FMT_ELF_HALF "\n", iSym, paSyms[iSym].st_shndx));
482	return VERR_BAD_EXE_FORMAT;
483	}
484	const char *pszName = ELF_STR(pModElf, paSyms[iSym].st_name);
485	if ( (pszName && *pszName)
486	&& ( (fFlags & RTLDR_ENUM_SYMBOL_FLAGS_ALL)
487	\|\| ELF_ST_BIND(paSyms[iSym].st_info) == STB_GLOBAL)
488	)
489	{
490	/*
491	* Call back.
492	*/
493	AssertMsgReturn(Value == (RTUINTPTR)Value, (FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG);
494	rc = pfnCallback(pMod, pszName, ~0, (RTUINTPTR)Value, pvUser);
495	if (rc)
496	return rc;
497	}
498	}
499	}
500
501	return VINF_SUCCESS;
502	}
503
504
505	/** @copydoc RTLDROPS::GetImageSize */
506	static DECLCALLBACK(size_t) RTLDRELF_NAME(GetImageSize)(PRTLDRMODINTERNAL pMod)
507	{
508	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
509
510	return pModElf->cbImage;
511	}
512
513
514	/** @copydoc RTLDROPS::GetBits */
515	static DECLCALLBACK(int) RTLDRELF_NAME(GetBits)(PRTLDRMODINTERNAL pMod, void pvBits, RTUINTPTR BaseAddress, PFNRTLDRIMPORT pfnGetImport, void pvUser)
516	{
517	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
518
519	/*
520	* This operation is currently only available on relocatable images.
521	*/
522	switch (pModElf->Ehdr.e_type)
523	{
524	case ET_REL:
525	break;
526	case ET_EXEC:
527	Log(("RTLdrELF: %s: Executable images are not supported yet!\n", pModElf->pReader->pfnLogName(pModElf->pReader)));
528	return VERR_LDRELF_EXEC;
529	case ET_DYN:
530	Log(("RTLdrELF: %s: Dynamic images are not supported yet!\n", pModElf->pReader->pfnLogName(pModElf->pReader)));
531	return VERR_LDRELF_DYN;
532	default: AssertFailedReturn(VERR_BAD_EXE_FORMAT);
533	}
534
535	/*
536	* Load the bits into pvBits.
537	*/
538	const Elf_Shdr *paShdrs = pModElf->paShdrs;
539	for (unsigned iShdr = 0; iShdr < pModElf->Ehdr.e_shnum; iShdr++)
540	{
541	if (paShdrs[iShdr].sh_flags & SHF_ALLOC)
542	{
543	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);
544	switch (paShdrs[iShdr].sh_type)
545	{
546	case SHT_NOBITS:
547	memset((uint8_t *)pvBits + paShdrs[iShdr].sh_addr, 0, (size_t)paShdrs[iShdr].sh_size);
548	break;
549
550	case SHT_PROGBITS:
551	default:
552	{
553	int rc = pModElf->pReader->pfnRead(pModElf->pReader, (uint8_t *)pvBits + paShdrs[iShdr].sh_addr,
554	(size_t)paShdrs[iShdr].sh_size, paShdrs[iShdr].sh_offset);
555	if (RT_FAILURE(rc))
556	{
557	Log(("RTLdrELF: %s: Read error when reading " FMT_ELF_SIZE " bytes at " FMT_ELF_OFF ", iShdr=%d\n",
558	pModElf->pReader->pfnLogName(pModElf->pReader),
559	paShdrs[iShdr].sh_size, paShdrs[iShdr].sh_offset, iShdr));
560	return rc;
561	}
562	}
563	}
564	}
565	}
566
567	/*
568	* Relocate the image.
569	*/
570	return pModElf->Core.pOps->pfnRelocate(pMod, pvBits, BaseAddress, ~(RTUINTPTR)0, pfnGetImport, pvUser);
571	}
572
573
574	/** @copydoc RTLDROPS::Relocate */
575	static DECLCALLBACK(int) RTLDRELF_NAME(Relocate)(PRTLDRMODINTERNAL pMod, void *pvBits, RTUINTPTR NewBaseAddress,
576	RTUINTPTR OldBaseAddress, PFNRTLDRIMPORT pfnGetImport, void *pvUser)
577	{
578	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
579	#ifdef LOG_ENABLED
580	const char *pszLogName = pModElf->pReader->pfnLogName(pModElf->pReader);
581	#endif
582	NOREF(OldBaseAddress);
583
584	/*
585	* This operation is currently only available on relocatable images.
586	*/
587	switch (pModElf->Ehdr.e_type)
588	{
589	case ET_REL:
590	break;
591	case ET_EXEC:
592	Log(("RTLdrELF: %s: Executable images are not supported yet!\n", pszLogName));
593	return VERR_LDRELF_EXEC;
594	case ET_DYN:
595	Log(("RTLdrELF: %s: Dynamic images are not supported yet!\n", pszLogName));
596	return VERR_LDRELF_DYN;
597	default: AssertFailedReturn(VERR_BAD_EXE_FORMAT);
598	}
599
600	/*
601	* Validate the input.
602	*/
603	Elf_Addr BaseAddr = (Elf_Addr)NewBaseAddress;
604	AssertMsgReturn((RTUINTPTR)BaseAddr == NewBaseAddress, ("#RTptr", NewBaseAddress), VERR_IMAGE_BASE_TOO_HIGH);
605
606	/*
607	* Map the image bits if not already done and setup pointer into it.
608	*/
609	int rc = RTLDRELF_NAME(MapBits)(pModElf, true);
610	if (RT_FAILURE(rc))
611	return rc;
612
613	/*
614	* Iterate the sections looking for interesting SHT_REL[A] sections.
615	* SHT_REL[A] sections have the section index of the section they contain fixups
616	* for in the sh_info member.
617	*/
618	const Elf_Shdr *paShdrs = pModElf->paShdrs;
619	Log2(("rtLdrElf: %s: Fixing up image\n", pszLogName));
620	for (unsigned iShdr = 0; iShdr < pModElf->Ehdr.e_shnum; iShdr++)
621	{
622	const Elf_Shdr *pShdrRel = &paShdrs[iShdr];
623
624	/*
625	* Skip sections without interest to us.
626	*/
627	#if ELF_MODE == 32
628	if (pShdrRel->sh_type != SHT_REL)
629	#else
630	if (pShdrRel->sh_type != SHT_RELA)
631	#endif
632	continue;
633	if (pShdrRel->sh_info >= pModElf->Ehdr.e_shnum)
634	continue;
635	const Elf_Shdr pShdr = &paShdrs[pShdrRel->sh_info]; / the section to fixup. */
636	if (!(pShdr->sh_flags & SHF_ALLOC))
637	continue;
638
639	/*
640	* Relocate the section.
641	*/
642	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",
643	pszLogName, (int)pShdrRel->sh_info, ELF_STR(pModElf, pShdr->sh_name), (int)pShdr->sh_info, (int)pShdr->sh_link,
644	iShdr, ELF_STR(pModElf, pShdrRel->sh_name), (int)pShdrRel->sh_info, (int)pShdrRel->sh_link));
645
646	/** @todo Make RelocateSection a function pointer so we can select the one corresponding to the machine when opening the image. */
647	rc = RTLDRELF_NAME(RelocateSection)(pModElf, BaseAddr, pfnGetImport, pvUser,
648	pShdr->sh_addr,
649	pShdr->sh_size,
650	(const uint8_t *)pModElf->pvBits + pShdr->sh_offset,
651	(uint8_t *)pvBits + pShdr->sh_addr,
652	(const uint8_t *)pModElf->pvBits + pShdrRel->sh_offset,
653	pShdrRel->sh_size);
654	if (RT_FAILURE(rc))
655	return rc;
656	}
657	return VINF_SUCCESS;
658	}
659
660
661	/** @copydoc RTLDROPS::pfnGetSymbolEx */
662	static DECLCALLBACK(int) RTLDRELF_NAME(GetSymbolEx)(PRTLDRMODINTERNAL pMod, const void pvBits, RTUINTPTR BaseAddress, const char pszSymbol, RTUINTPTR *pValue)
663	{
664	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
665	NOREF(pvBits);
666
667	/*
668	* Validate the input.
669	*/
670	Elf_Addr BaseAddr = (Elf_Addr)BaseAddress;
671	AssertMsgReturn((RTUINTPTR)BaseAddr == BaseAddress, ("#RTptr", BaseAddress), VERR_IMAGE_BASE_TOO_HIGH);
672
673	/*
674	* Map the image bits if not already done and setup pointer into it.
675	*/
676	int rc = RTLDRELF_NAME(MapBits)(pModElf, true);
677	if (RT_FAILURE(rc))
678	return rc;
679
680	/*
681	* Calc all kinds of pointers before we start iterating the symbol table.
682	*/
683	const char *pStr = pModElf->pStr;
684	const Elf_Sym *paSyms = pModElf->paSyms;
685	unsigned cSyms = pModElf->cSyms;
686	for (unsigned iSym = 1; iSym < cSyms; iSym++)
687	{
688	/* Undefined symbols are not exports, they are imports. */
689	if ( paSyms[iSym].st_shndx != SHN_UNDEF
690	&& ( ELF_ST_BIND(paSyms[iSym].st_info) == STB_GLOBAL
691	\|\| ELF_ST_BIND(paSyms[iSym].st_info) == STB_WEAK))
692	{
693	/* Validate the name string and try match with it. */
694	if (paSyms[iSym].st_name < pModElf->cbStr)
695	{
696	if (!strcmp(pszSymbol, pStr + paSyms[iSym].st_name))
697	{
698	/* matched! */
699	Elf_Addr Value;
700	if (paSyms[iSym].st_shndx == SHN_ABS)
701	/* absolute symbols are not subject to any relocation. */
702	Value = paSyms[iSym].st_value;
703	else if (paSyms[iSym].st_shndx < pModElf->Ehdr.e_shnum)
704	/* relative to the section. */
705	Value = BaseAddr + paSyms[iSym].st_value + pModElf->paShdrs[paSyms[iSym].st_shndx].sh_addr;
706	else
707	{
708	AssertMsgFailed(("Arg. paSyms[iSym].st_shndx=%d\n", paSyms[iSym].st_shndx));
709	return VERR_BAD_EXE_FORMAT;
710	}
711	AssertMsgReturn(Value == (RTUINTPTR)Value, (FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG);
712	*pValue = (RTUINTPTR)Value;
713	return VINF_SUCCESS;
714	}
715	}
716	else
717	{
718	AssertMsgFailed(("String outside string table! iSym=%d paSyms[iSym].st_name=%#x\n", iSym, paSyms[iSym].st_name));
719	return VERR_LDRELF_INVALID_SYMBOL_NAME_OFFSET;
720	}
721	}
722	}
723
724	return VERR_SYMBOL_NOT_FOUND;
725	}
726
727
728	/** @copydoc RTLDROPS::pfnEnumDbgInfo */
729	static DECLCALLBACK(int) RTLDRELF_NAME(EnumDbgInfo)(PRTLDRMODINTERNAL pMod, const void *pvBits,
730	PFNRTLDRENUMDBG pfnCallback, void *pvUser)
731	{
732	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
733	NOREF(pvBits);
734
735	return VERR_NOT_IMPLEMENTED; NOREF(pModElf); NOREF(pfnCallback); NOREF(pvUser);
736	}
737
738
739	/** @copydoc RTLDROPS::pfnEnumSegments. */
740	static DECLCALLBACK(int) RTLDRELF_NAME(EnumSegments)(PRTLDRMODINTERNAL pMod, PFNRTLDRENUMSEGS pfnCallback, void *pvUser)
741	{
742	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
743
744	return VERR_NOT_IMPLEMENTED; NOREF(pModElf); NOREF(pfnCallback); NOREF(pvUser);
745	}
746
747
748	/** @copydoc RTLDROPS::pfnLinkAddressToSegOffset. */
749	static DECLCALLBACK(int) RTLDRELF_NAME(LinkAddressToSegOffset)(PRTLDRMODINTERNAL pMod, RTLDRADDR LinkAddress,
750	uint32_t *piSeg, PRTLDRADDR poffSeg)
751	{
752	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
753
754	return VERR_NOT_IMPLEMENTED; NOREF(pModElf); NOREF(LinkAddress); NOREF(piSeg); NOREF(poffSeg);
755	}
756
757
758	/** @copydoc RTLDROPS::pfnLinkAddressToRva. */
759	static DECLCALLBACK(int) RTLDRELF_NAME(LinkAddressToRva)(PRTLDRMODINTERNAL pMod, RTLDRADDR LinkAddress, PRTLDRADDR pRva)
760	{
761	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
762
763	return VERR_NOT_IMPLEMENTED; NOREF(pModElf); NOREF(LinkAddress); NOREF(pRva);
764	}
765
766
767	/** @copydoc RTLDROPS::pfnSegOffsetToRva. */
768	static DECLCALLBACK(int) RTLDRELF_NAME(SegOffsetToRva)(PRTLDRMODINTERNAL pMod, uint32_t iSeg, RTLDRADDR offSeg,
769	PRTLDRADDR pRva)
770	{
771	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
772
773	return VERR_NOT_IMPLEMENTED; NOREF(pModElf); NOREF(iSeg); NOREF(offSeg); NOREF(pRva);
774	}
775
776
777	/** @copydoc RTLDROPS::pfnRvaToSegOffset. */
778	static DECLCALLBACK(int) RTLDRELF_NAME(RvaToSegOffset)(PRTLDRMODINTERNAL pMod, RTLDRADDR Rva,
779	uint32_t *piSeg, PRTLDRADDR poffSeg)
780	{
781	PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
782
783	return VERR_NOT_IMPLEMENTED; NOREF(pModElf); NOREF(Rva); NOREF(piSeg); NOREF(poffSeg);
784	}
785
786
787
788	/**
789	* The ELF module operations.
790	*/
791	static RTLDROPS RTLDRELF_MID(s_rtldrElf,Ops) =
792	{
793	#if ELF_MODE == 32
794	"elf32",
795	#elif ELF_MODE == 64
796	"elf64",
797	#endif
798	RTLDRELF_NAME(Close),
799	NULL, /* Get Symbol */
800	RTLDRELF_NAME(Done),
801	RTLDRELF_NAME(EnumSymbols),
802	/* ext: */
803	RTLDRELF_NAME(GetImageSize),
804	RTLDRELF_NAME(GetBits),
805	RTLDRELF_NAME(Relocate),
806	RTLDRELF_NAME(GetSymbolEx),
807	RTLDRELF_NAME(EnumDbgInfo),
808	RTLDRELF_NAME(EnumSegments),
809	RTLDRELF_NAME(LinkAddressToSegOffset),
810	RTLDRELF_NAME(LinkAddressToRva),
811	RTLDRELF_NAME(SegOffsetToRva),
812	RTLDRELF_NAME(RvaToSegOffset),
813	42
814	};
815
816
817
818	/**
819	* Validates the ELF header.
820	*
821	* @returns iprt status code.
822	* @param pEhdr Pointer to the ELF header.
823	* @param pszLogName The log name.
824	* @param cbRawImage The size of the raw image.
825	*/
826	static int RTLDRELF_NAME(ValidateElfHeader)(const Elf_Ehdr pEhdr, const char pszLogName, uint64_t cbRawImage,
827	PRTLDRARCH penmArch)
828	{
829	Log3(("RTLdrELF: e_ident: %.*Rhxs\n"
830	"RTLdrELF: e_type: " FMT_ELF_HALF "\n"
831	"RTLdrELF: e_version: " FMT_ELF_HALF "\n"
832	"RTLdrELF: e_entry: " FMT_ELF_ADDR "\n"
833	"RTLdrELF: e_phoff: " FMT_ELF_OFF "\n"
834	"RTLdrELF: e_shoff: " FMT_ELF_OFF "\n"
835	"RTLdrELF: e_flags: " FMT_ELF_WORD "\n"
836	"RTLdrELF: e_ehsize: " FMT_ELF_HALF "\n"
837	"RTLdrELF: e_phentsize: " FMT_ELF_HALF "\n"
838	"RTLdrELF: e_phnum: " FMT_ELF_HALF "\n"
839	"RTLdrELF: e_shentsize: " FMT_ELF_HALF "\n"
840	"RTLdrELF: e_shnum: " FMT_ELF_HALF "\n"
841	"RTLdrELF: e_shstrndx: " FMT_ELF_HALF "\n",
842	RT_ELEMENTS(pEhdr->e_ident), &pEhdr->e_ident[0], pEhdr->e_type, pEhdr->e_version,
843	pEhdr->e_entry, pEhdr->e_phoff, pEhdr->e_shoff,pEhdr->e_flags, pEhdr->e_ehsize, pEhdr->e_phentsize,
844	pEhdr->e_phnum, pEhdr->e_shentsize, pEhdr->e_shnum, pEhdr->e_shstrndx));
845
846	if ( pEhdr->e_ident[EI_MAG0] != ELFMAG0
847	\|\| pEhdr->e_ident[EI_MAG1] != ELFMAG1
848	\|\| pEhdr->e_ident[EI_MAG2] != ELFMAG2
849	\|\| pEhdr->e_ident[EI_MAG3] != ELFMAG3
850	)
851	{
852	Log(("RTLdrELF: %s: Invalid ELF magic (%.*Rhxs)\n", pszLogName, sizeof(pEhdr->e_ident), pEhdr->e_ident)); NOREF(pszLogName);
853	return VERR_BAD_EXE_FORMAT;
854	}
855	if (pEhdr->e_ident[EI_CLASS] != RTLDRELF_SUFF(ELFCLASS))
856	{
857	Log(("RTLdrELF: %s: Invalid ELF class (%.*Rhxs)\n", pszLogName, sizeof(pEhdr->e_ident), pEhdr->e_ident));
858	return VERR_BAD_EXE_FORMAT;
859	}
860	if (pEhdr->e_ident[EI_DATA] != ELFDATA2LSB)
861	{
862	Log(("RTLdrELF: %s: ELF endian %x is unsupported\n", pEhdr->e_ident[EI_DATA]));
863	return VERR_LDRELF_ODD_ENDIAN;
864	}
865	if (pEhdr->e_version != EV_CURRENT)
866	{
867	Log(("RTLdrELF: %s: ELF version %x is unsupported\n", pEhdr->e_version));
868	return VERR_LDRELF_VERSION;
869	}
870
871	if (sizeof(Elf_Ehdr) != pEhdr->e_ehsize)
872	{
873	Log(("RTLdrELF: %s: Elf header e_ehsize is %d expected %d!\n",
874	pszLogName, pEhdr->e_ehsize, sizeof(Elf_Ehdr)));
875	return VERR_BAD_EXE_FORMAT;
876	}
877	if ( sizeof(Elf_Phdr) != pEhdr->e_phentsize
878	&& ( pEhdr->e_phnum != 0
879	\|\| pEhdr->e_type == ET_DYN))
880	{
881	Log(("RTLdrELF: %s: Elf header e_phentsize is %d expected %d!\n",
882	pszLogName, pEhdr->e_phentsize, sizeof(Elf_Phdr)));
883	return VERR_BAD_EXE_FORMAT;
884	}
885	if (sizeof(Elf_Shdr) != pEhdr->e_shentsize)
886	{
887	Log(("RTLdrELF: %s: Elf header e_shentsize is %d expected %d!\n",
888	pszLogName, pEhdr->e_shentsize, sizeof(Elf_Shdr)));
889	return VERR_BAD_EXE_FORMAT;
890	}
891
892	switch (pEhdr->e_type)
893	{
894	case ET_REL:
895	case ET_EXEC:
896	case ET_DYN:
897	break;
898	default:
899	Log(("RTLdrELF: %s: image type %#x is not supported!\n", pszLogName, pEhdr->e_type));
900	return VERR_BAD_EXE_FORMAT;
901	}
902
903	switch (pEhdr->e_machine)
904	{
905	#if ELF_MODE == 32
906	case EM_386:
907	case EM_486:
908	*penmArch = RTLDRARCH_X86_32;
909	break;
910	#elif ELF_MODE == 64
911	case EM_X86_64:
912	*penmArch = RTLDRARCH_AMD64;
913	break;
914	#endif
915	default:
916	Log(("RTLdrELF: %s: machine type %u is not supported!\n", pEhdr->e_machine));
917	return VERR_LDRELF_MACHINE;
918	}
919
920	if ( pEhdr->e_phoff < pEhdr->e_ehsize
921	&& !(pEhdr->e_phoff && pEhdr->e_phnum)
922	&& pEhdr->e_phnum)
923	{
924	Log(("RTLdrELF: %s: The program headers overlap with the ELF header! e_phoff=" FMT_ELF_OFF "\n",
925	pszLogName, pEhdr->e_phoff));
926	return VERR_BAD_EXE_FORMAT;
927	}
928	if ( pEhdr->e_phoff + pEhdr->e_phnum * pEhdr->e_phentsize > cbRawImage
929	\|\| pEhdr->e_phoff + pEhdr->e_phnum * pEhdr->e_phentsize < pEhdr->e_phoff)
930	{
931	Log(("RTLdrELF: %s: The program headers extends beyond the file! e_phoff=" FMT_ELF_OFF " e_phnum=" FMT_ELF_HALF "\n",
932	pszLogName, pEhdr->e_phoff, pEhdr->e_phnum));
933	return VERR_BAD_EXE_FORMAT;
934	}
935
936
937	if ( pEhdr->e_shoff < pEhdr->e_ehsize
938	&& !(pEhdr->e_shoff && pEhdr->e_shnum))
939	{
940	Log(("RTLdrELF: %s: The section headers overlap with the ELF header! e_shoff=" FMT_ELF_OFF "\n",
941	pszLogName, pEhdr->e_shoff));
942	return VERR_BAD_EXE_FORMAT;
943	}
944	if ( pEhdr->e_shoff + pEhdr->e_shnum * pEhdr->e_shentsize > cbRawImage
945	\|\| pEhdr->e_shoff + pEhdr->e_shnum * pEhdr->e_shentsize < pEhdr->e_shoff)
946	{
947	Log(("RTLdrELF: %s: The section headers extends beyond the file! e_shoff=" FMT_ELF_OFF " e_shnum=" FMT_ELF_HALF "\n",
948	pszLogName, pEhdr->e_shoff, pEhdr->e_shnum));
949	return VERR_BAD_EXE_FORMAT;
950	}
951
952	return VINF_SUCCESS;
953	}
954
955	/**
956	* Gets the section header name.
957	*
958	* @returns pszName.
959	* @param pReader The loader reader instance.
960	* @param pEhdr The elf header.
961	* @param offName The offset of the section header name.
962	* @param pszName Where to store the name.
963	* @param cbName The size of the buffer pointed to by pszName.
964	*/
965	const char RTLDRELF_NAME(GetSHdrName)(PRTLDRMODELF pModElf, Elf_Word offName, char pszName, size_t cbName)
966	{
967	RTFOFF off = pModElf->paShdrs[pModElf->Ehdr.e_shstrndx].sh_offset + offName;
968	int rc = pModElf->pReader->pfnRead(pModElf->pReader, pszName, cbName - 1, off);
969	if (RT_FAILURE(rc))
970	{
971	/* read by for byte. */
972	for (unsigned i = 0; i < cbName; i++, off++)
973	{
974	rc = pModElf->pReader->pfnRead(pModElf->pReader, pszName + i, 1, off);
975	if (RT_FAILURE(rc))
976	{
977	pszName[i] = '\0';
978	break;
979	}
980	}
981	}
982
983	pszName[cbName - 1] = '\0';
984	return pszName;
985	}
986
987
988	/**
989	* Validates a section header.
990	*
991	* @returns iprt status code.
992	* @param pModElf Pointer to the module structure.
993	* @param iShdr The index of section header which should be validated.
994	* The section headers are found in the pModElf->paShdrs array.
995	* @param pszLogName The log name.
996	* @param cbRawImage The size of the raw image.
997	*/
998	static int RTLDRELF_NAME(ValidateSectionHeader)(PRTLDRMODELF pModElf, unsigned iShdr, const char *pszLogName, RTFOFF cbRawImage)
999	{
1000	const Elf_Shdr *pShdr = &pModElf->paShdrs[iShdr];
1001	char szSectionName[80]; NOREF(szSectionName);
1002	Log3(("RTLdrELF: Section Header #%d:\n"
1003	"RTLdrELF: sh_name: " FMT_ELF_WORD " - %s\n"
1004	"RTLdrELF: sh_type: " FMT_ELF_WORD " (%s)\n"
1005	"RTLdrELF: sh_flags: " FMT_ELF_XWORD "\n"
1006	"RTLdrELF: sh_addr: " FMT_ELF_ADDR "\n"
1007	"RTLdrELF: sh_offset: " FMT_ELF_OFF "\n"
1008	"RTLdrELF: sh_size: " FMT_ELF_XWORD "\n"
1009	"RTLdrELF: sh_link: " FMT_ELF_WORD "\n"
1010	"RTLdrELF: sh_info: " FMT_ELF_WORD "\n"
1011	"RTLdrELF: sh_addralign: " FMT_ELF_XWORD "\n"
1012	"RTLdrELF: sh_entsize: " FMT_ELF_XWORD "\n",
1013	iShdr,
1014	pShdr->sh_name, RTLDRELF_NAME(GetSHdrName)(pModElf, pShdr->sh_name, szSectionName, sizeof(szSectionName)),
1015	pShdr->sh_type, rtldrElfGetShdrType(pShdr->sh_type), pShdr->sh_flags, pShdr->sh_addr,
1016	pShdr->sh_offset, pShdr->sh_size, pShdr->sh_link, pShdr->sh_info, pShdr->sh_addralign,
1017	pShdr->sh_entsize));
1018
1019	if (pShdr->sh_link >= pModElf->Ehdr.e_shnum)
1020	{
1021	Log(("RTLdrELF: %s: Shdr #%d: sh_link (%d) is beyond the end of the section table (%d)!\n",
1022	pszLogName, iShdr, pShdr->sh_link, pModElf->Ehdr.e_shnum)); NOREF(pszLogName);
1023	return VERR_BAD_EXE_FORMAT;
1024	}
1025
1026	switch (pShdr->sh_type)
1027	{
1028	/** @todo find specs and check up which sh_info fields indicates section table entries */
1029	case 12301230:
1030	if (pShdr->sh_info >= pModElf->Ehdr.e_shnum)
1031	{
1032	Log(("RTLdrELF: %s: Shdr #%d: sh_info (%d) is beyond the end of the section table (%d)!\n",
1033	pszLogName, iShdr, pShdr->sh_link, pModElf->Ehdr.e_shnum));
1034	return VERR_BAD_EXE_FORMAT;
1035	}
1036	break;
1037
1038	case SHT_NULL:
1039	case SHT_PROGBITS:
1040	case SHT_SYMTAB:
1041	case SHT_STRTAB:
1042	case SHT_RELA:
1043	case SHT_HASH:
1044	case SHT_DYNAMIC:
1045	case SHT_NOTE:
1046	case SHT_NOBITS:
1047	case SHT_REL:
1048	case SHT_SHLIB:
1049	case SHT_DYNSYM:
1050	/*
1051	* For these types sh_info doesn't have any special meaning, or anything which
1052	* we need/can validate now.
1053	*/
1054	break;
1055
1056
1057	default:
1058	Log(("RTLdrELF: %s: Warning, unknown type %d!\n", pszLogName, pShdr->sh_type));
1059	break;
1060	}
1061
1062	if ( pShdr->sh_type != SHT_NOBITS
1063	&& pShdr->sh_size)
1064	{
1065	RTFOFF offEnd = pShdr->sh_offset + pShdr->sh_size;
1066	if ( offEnd > cbRawImage
1067	\|\| offEnd < (RTFOFF)pShdr->sh_offset)
1068	{
1069	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",
1070	pszLogName, iShdr, pShdr->sh_offset, pShdr->sh_size, offEnd, cbRawImage));
1071	return VERR_BAD_EXE_FORMAT;
1072	}
1073	if (pShdr->sh_offset < sizeof(Elf_Ehdr))
1074	{
1075	Log(("RTLdrELF: %s: Shdr #%d: sh_offset (" FMT_ELF_OFF ") + sh_size (" FMT_ELF_XWORD ") is starting in the ELF header!\n",
1076	pszLogName, iShdr, pShdr->sh_offset, pShdr->sh_size, cbRawImage));
1077	return VERR_BAD_EXE_FORMAT;
1078	}
1079	}
1080
1081	return VINF_SUCCESS;
1082	}
1083
1084
1085
1086	/**
1087	* Opens an ELF image, fixed bitness.
1088	*
1089	* @returns iprt status code.
1090	* @param pReader The loader reader instance which will provide the raw image bits.
1091	* @param fFlags Reserved, MBZ.
1092	* @param enmArch Architecture specifier.
1093	* @param phLdrMod Where to store the handle.
1094	*/
1095	static int RTLDRELF_NAME(Open)(PRTLDRREADER pReader, uint32_t fFlags, RTLDRARCH enmArch, PRTLDRMOD phLdrMod)
1096	{
1097	const char *pszLogName = pReader->pfnLogName(pReader);
1098	RTFOFF cbRawImage = pReader->pfnSize(pReader);
1099	AssertReturn(!fFlags, VERR_INVALID_PARAMETER);
1100
1101	/*
1102	* Create the loader module instance.
1103	*/
1104	PRTLDRMODELF pModElf = (PRTLDRMODELF)RTMemAllocZ(sizeof(*pModElf));
1105	if (!pModElf)
1106	return VERR_NO_MEMORY;
1107
1108	pModElf->Core.u32Magic = RTLDRMOD_MAGIC;
1109	pModElf->Core.eState = LDR_STATE_INVALID;
1110	pModElf->pReader = pReader;
1111	//pModElf->pvBits = NULL;
1112	//pModElf->Ehdr = {0};
1113	//pModElf->paShdrs = NULL;
1114	//pModElf->paSyms = NULL;
1115	pModElf->iSymSh = ~0U;
1116	pModElf->cSyms = 0;
1117	pModElf->iStrSh = ~0U;
1118	pModElf->cbStr = 0;
1119	pModElf->cbImage = 0;
1120	//pModElf->pStr = NULL;
1121
1122	/*
1123	* Read and validate the ELF header and match up the CPU architecture.
1124	*/
1125	int rc = pReader->pfnRead(pReader, &pModElf->Ehdr, sizeof(pModElf->Ehdr), 0);
1126	if (RT_SUCCESS(rc))
1127	{
1128	RTLDRARCH enmArchImage = RTLDRARCH_INVALID; /* shut up gcc */
1129	rc = RTLDRELF_NAME(ValidateElfHeader)(&pModElf->Ehdr, pszLogName, cbRawImage, &enmArchImage);
1130	if (RT_SUCCESS(rc))
1131	{
1132	if ( enmArch != RTLDRARCH_WHATEVER
1133	&& enmArch != enmArchImage)
1134	rc = VERR_LDR_ARCH_MISMATCH;
1135	}
1136	}
1137	if (RT_SUCCESS(rc))
1138	{
1139	/*
1140	* Read the section headers.
1141	*/
1142	Elf_Shdr paShdrs = (Elf_Shdr )RTMemAlloc(pModElf->Ehdr.e_shnum * sizeof(Elf_Shdr));
1143	if (paShdrs)
1144	{
1145	pModElf->paShdrs = paShdrs;
1146	rc = pReader->pfnRead(pReader, paShdrs, pModElf->Ehdr.e_shnum * sizeof(Elf_Shdr),
1147	pModElf->Ehdr.e_shoff);
1148	if (RT_SUCCESS(rc))
1149	{
1150	/*
1151	* Validate the section headers, allocate memory for the sections (determine the image size),
1152	* and find relevant sections.
1153	*/
1154	for (unsigned i = 0; i < pModElf->Ehdr.e_shnum; i++)
1155	{
1156	rc = RTLDRELF_NAME(ValidateSectionHeader)(pModElf, i, pszLogName, cbRawImage);
1157	if (RT_FAILURE(rc))
1158	break;
1159
1160	/* Allocate memory addresses for the section. */
1161	if (paShdrs[i].sh_flags & SHF_ALLOC)
1162	{
1163	paShdrs[i].sh_addr = paShdrs[i].sh_addralign
1164	? RT_ALIGN_T(pModElf->cbImage, paShdrs[i].sh_addralign, Elf_Addr)
1165	: (Elf_Addr)pModElf->cbImage;
1166	pModElf->cbImage = (size_t)paShdrs[i].sh_addr + (size_t)paShdrs[i].sh_size;
1167	AssertMsgReturn(pModElf->cbImage == paShdrs[i].sh_addr + paShdrs[i].sh_size,
1168	(FMT_ELF_ADDR "\n", paShdrs[i].sh_addr + paShdrs[i].sh_size),
1169	VERR_IMAGE_TOO_BIG);
1170	Log2(("RTLdrElf: %s: Assigned " FMT_ELF_ADDR " to section #%d\n", pszLogName, paShdrs[i].sh_addr, i));
1171	}
1172
1173	/* We're looking for symbol tables. */
1174	if (paShdrs[i].sh_type == SHT_SYMTAB)
1175	{
1176	if (pModElf->iSymSh != ~0U)
1177	{
1178	Log(("RTLdrElf: %s: Multiple symbol tabs! iSymSh=%d i=%d\n", pszLogName, pModElf->iSymSh, i));
1179	rc = VERR_LDRELF_MULTIPLE_SYMTABS;
1180	break;
1181	}
1182	pModElf->iSymSh = i;
1183	pModElf->cSyms = (unsigned)(paShdrs[i].sh_size / sizeof(Elf_Sym));
1184	AssertReturn(pModElf->cSyms == paShdrs[i].sh_size / sizeof(Elf_Sym), VERR_IMAGE_TOO_BIG);
1185	pModElf->iStrSh = paShdrs[i].sh_link;
1186	pModElf->cbStr = (unsigned)paShdrs[pModElf->iStrSh].sh_size;
1187	AssertReturn(pModElf->cbStr == paShdrs[pModElf->iStrSh].sh_size, VERR_IMAGE_TOO_BIG);
1188	}
1189	} /* for each section header */
1190
1191	Log2(("RTLdrElf: iSymSh=%u cSyms=%u iStrSh=%u cbStr=%u rc=%Rrc cbImage=%#zx\n",
1192	pModElf->iSymSh, pModElf->cSyms, pModElf->iStrSh, pModElf->cbStr, rc, pModElf->cbImage));
1193	#if 0
1194	/*
1195	* Are the section headers fine?
1196	* We require there to be symbol & string tables (at least for the time being).
1197	*/
1198	if ( pModElf->iSymSh == ~0U
1199	\|\| pModElf->iStrSh == ~0U)
1200	rc = VERR_LDRELF_NO_SYMBOL_OR_NO_STRING_TABS;
1201	#endif
1202	if (RT_SUCCESS(rc))
1203	{
1204	pModElf->Core.pOps = &RTLDRELF_MID(s_rtldrElf,Ops);
1205	pModElf->Core.eState = LDR_STATE_OPENED;
1206	*phLdrMod = &pModElf->Core;
1207
1208	LogFlow(("%s: %s: returns VINF_SUCCESS phLdrMod=%p\n", __FUNCTION__, pszLogName, phLdrMod));
1209	return VINF_SUCCESS;
1210	}
1211	}
1212
1213	RTMemFree(paShdrs);
1214	}
1215	else
1216	rc = VERR_NO_MEMORY;
1217	}
1218
1219	RTMemFree(pModElf);
1220	LogFlow(("%s: returns %Rrc\n", __FUNCTION__, rc));
1221	return rc;
1222	}
1223
1224
1225
1226
1227	/*******************************************************************************
1228	* Cleanup Constants And Macros *
1229	*******************************************************************************/
1230	#undef RTLDRELF_NAME
1231	#undef RTLDRELF_SUFF
1232	#undef RTLDRELF_MID
1233
1234	#undef FMT_ELF_ADDR
1235	#undef FMT_ELF_HALF
1236	#undef FMT_ELF_SHALF
1237	#undef FMT_ELF_OFF
1238	#undef FMT_ELF_SIZE
1239	#undef FMT_ELF_SWORD
1240	#undef FMT_ELF_WORD
1241	#undef FMT_ELF_XWORD
1242	#undef FMT_ELF_SXWORD
1243
1244	#undef Elf_Ehdr
1245	#undef Elf_Phdr
1246	#undef Elf_Shdr
1247	#undef Elf_Sym
1248	#undef Elf_Rel
1249	#undef Elf_Rela
1250	#undef Elf_Reloc
1251	#undef Elf_Nhdr
1252	#undef Elf_Dyn
1253
1254	#undef Elf_Addr
1255	#undef Elf_Half
1256	#undef Elf_Off
1257	#undef Elf_Size
1258	#undef Elf_Sword
1259	#undef Elf_Word
1260
1261	#undef RTLDRMODELF
1262	#undef PRTLDRMODELF
1263
1264	#undef ELF_R_SYM
1265	#undef ELF_R_TYPE
1266	#undef ELF_R_INFO
1267
1268	#undef ELF_ST_BIND
1269

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source: vbox/trunk/src/VBox/Runtime/common/ldr/ldrELFRelocatable.cpp.h@ 42599

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