VirtualBox

source: vbox/trunk/src/VBox/Runtime/common/ldr/ldrELFRelocatable.cpp.h@ 25000

Last change on this file since 25000 was 25000, checked in by vboxsync, 15 years ago

IPRT: Fixed -Wshadow warnings, found two bugs in error paths.

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1/* $Id: ldrELFRelocatable.cpp.h 25000 2009-11-26 14:22:44Z vboxsync $ */
2/** @file
3 * IPRT - Binary Image Loader, Template for ELF Relocatable Images.
4 */
5
6/*
7 * Copyright (C) 2006-2007 Sun Microsystems, Inc.
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 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
27 * Clara, CA 95054 USA or visit http://www.sun.com if you need
28 * additional information or have any questions.
29 */
30
31
32/*******************************************************************************
33* Defined Constants And Macros *
34*******************************************************************************/
35#if ELF_MODE == 32
36#define RTLDRELF_NAME(name) rtldrELF32##name
37#define RTLDRELF_SUFF(name) name##32
38#define RTLDRELF_MID(pre,suff) pre##32##suff
39#define FMT_ELF_ADDR "%08RX32"
40#define FMT_ELF_HALF "%04RX16"
41#define FMT_ELF_OFF "%08RX32"
42#define FMT_ELF_SIZE "%08RX32"
43#define FMT_ELF_SWORD "%RI32"
44#define FMT_ELF_WORD "%08RX32"
45#define FMT_ELF_XWORD "%08RX32"
46#define FMT_ELF_SXWORD "%RI32"
47
48#elif ELF_MODE == 64
49#define RTLDRELF_NAME(name) rtldrELF64##name
50#define RTLDRELF_SUFF(name) name##64
51#define RTLDRELF_MID(pre,suff) pre##64##suff
52#define FMT_ELF_ADDR "%016RX64"
53#define FMT_ELF_HALF "%04RX16"
54#define FMT_ELF_SHALF "%RI16"
55#define FMT_ELF_OFF "%016RX64"
56#define FMT_ELF_SIZE "%016RX64"
57#define FMT_ELF_SWORD "%RI32"
58#define FMT_ELF_WORD "%08RX32"
59#define FMT_ELF_XWORD "%016RX64"
60#define FMT_ELF_SXWORD "%RI64"
61#endif
62
63#define Elf_Ehdr RTLDRELF_MID(Elf,_Ehdr)
64#define Elf_Phdr RTLDRELF_MID(Elf,_Phdr)
65#define Elf_Shdr RTLDRELF_MID(Elf,_Shdr)
66#define Elf_Sym RTLDRELF_MID(Elf,_Sym)
67#define Elf_Rel RTLDRELF_MID(Elf,_Rel)
68#define Elf_Rela RTLDRELF_MID(Elf,_Rela)
69#define Elf_Nhdr RTLDRELF_MID(Elf,_Nhdr)
70#define Elf_Dyn RTLDRELF_MID(Elf,_Dyn)
71#define Elf_Addr RTLDRELF_MID(Elf,_Addr)
72#define Elf_Half RTLDRELF_MID(Elf,_Half)
73#define Elf_Off RTLDRELF_MID(Elf,_Off)
74#define Elf_Size RTLDRELF_MID(Elf,_Size)
75#define Elf_Sword RTLDRELF_MID(Elf,_Sword)
76#define Elf_Word RTLDRELF_MID(Elf,_Word)
77
78#define RTLDRMODELF RTLDRELF_MID(RTLDRMODELF,RT_NOTHING)
79#define PRTLDRMODELF RTLDRELF_MID(PRTLDRMODELF,RT_NOTHING)
80
81#define ELF_R_SYM(info) RTLDRELF_MID(ELF,_R_SYM)(info)
82#define ELF_R_TYPE(info) RTLDRELF_MID(ELF,_R_TYPE)(info)
83#define ELF_R_INFO(sym, type) RTLDRELF_MID(ELF,_R_INFO)(sym, type)
84
85#define ELF_ST_BIND(info) RTLDRELF_MID(ELF,_ST_BIND)(info)
86
87
88
89/*******************************************************************************
90* Structures and Typedefs *
91*******************************************************************************/
92/**
93 * The ELF loader structure.
94 */
95typedef struct RTLDRMODELF
96{
97 /** Core module structure. */
98 RTLDRMODINTERNAL Core;
99 /** Pointer to the reader instance. */
100 PRTLDRREADER pReader;
101 /** Pointer to readonly mapping of the image bits.
102 * This mapping is provided by the pReader. */
103 const void *pvBits;
104
105 /** The ELF header. */
106 Elf_Ehdr Ehdr;
107 /** Pointer to our copy of the section headers.
108 * The virtual addresses in this array is the 0 based assignments we've given the image.
109 * Not valid if the image is DONE. */
110 Elf_Shdr *paShdrs;
111 /** The size of the loaded image. */
112 size_t cbImage;
113
114 /** The symbol section index. */
115 unsigned iSymSh;
116 /** Number of symbols in the table. */
117 unsigned cSyms;
118 /** Pointer to symbol table within RTLDRMODELF::pvBits. */
119 const Elf_Sym *paSyms;
120
121 /** The string section index. */
122 unsigned iStrSh;
123 /** Size of the string table. */
124 unsigned cbStr;
125 /** Pointer to string table within RTLDRMODELF::pvBits. */
126 const char *pStr;
127} RTLDRMODELF, *PRTLDRMODELF;
128
129
130/**
131 * Maps the image bits into memory and resolve pointers into it.
132 *
133 * @returns iprt status code.
134 * @param pModElf The ELF loader module instance data.
135 * @param fNeedsBits Set if we actually need the pvBits member.
136 * If we don't, we can simply read the string and symbol sections, thus saving memory.
137 */
138static int RTLDRELF_NAME(MapBits)(PRTLDRMODELF pModElf, bool fNeedsBits)
139{
140 NOREF(fNeedsBits);
141 if (pModElf->pvBits)
142 return VINF_SUCCESS;
143 int rc = pModElf->pReader->pfnMap(pModElf->pReader, &pModElf->pvBits);
144 if (RT_SUCCESS(rc))
145 {
146 const uint8_t *pu8 = (const uint8_t *)pModElf->pvBits;
147 pModElf->paSyms = (const Elf_Sym *)(pu8 + pModElf->paShdrs[pModElf->iSymSh].sh_offset);
148 pModElf->pStr = (const char *)(pu8 + pModElf->paShdrs[pModElf->iStrSh].sh_offset);
149 }
150 return rc;
151}
152
153
154/**
155 * Get the symbol and symbol value.
156 *
157 * @returns iprt status code.
158 * @param pModElf The ELF loader module instance data.
159 * @param BaseAddr The base address which the module is being fixedup to.
160 * @param pfnGetImport The callback function to use to resolve imports (aka unresolved externals).
161 * @param pvUser User argument to pass to the callback.
162 * @param iSym The symbol to get.
163 * @param ppSym Where to store the symbol pointer on success. (read only)
164 * @param pSymValue Where to store the symbol value on success.
165 */
166static int RTLDRELF_NAME(Symbol)(PRTLDRMODELF pModElf, Elf_Addr BaseAddr, PFNRTLDRIMPORT pfnGetImport, void *pvUser,
167 Elf_Size iSym, const Elf_Sym **ppSym, Elf_Addr *pSymValue)
168{
169 /*
170 * Validate and find the symbol.
171 */
172 if (iSym >= pModElf->cSyms)
173 {
174 AssertMsgFailed(("iSym=%d is an invalid symbol index!\n", iSym));
175 return VERR_LDRELF_INVALID_SYMBOL_INDEX;
176 }
177 const Elf_Sym *pSym = &pModElf->paSyms[iSym];
178 *ppSym = pSym;
179
180 if (pSym->st_name >= pModElf->cbStr)
181 {
182 AssertMsgFailed(("iSym=%d st_name=%d str sh_size=%d\n", iSym, pSym->st_name, pModElf->cbStr));
183 return VERR_LDRELF_INVALID_SYMBOL_NAME_OFFSET;
184 }
185 const char *pszName = ELF_STR(pModElf, pSym->st_name);
186
187 /*
188 * Determin the symbol value.
189 *
190 * Symbols needs different treatment depending on which section their are in.
191 * Undefined and absolute symbols goes into special non-existing sections.
192 */
193 switch (pSym->st_shndx)
194 {
195 /*
196 * Undefined symbol, needs resolving.
197 *
198 * Since ELF has no generic concept of importing from specific module (the OS/2 ELF format
199 * has but that's a OS extension and only applies to programs and dlls), we'll have to ask
200 * the resolver callback to do a global search.
201 */
202 case SHN_UNDEF:
203 {
204 /* Try to resolve the symbol. */
205 RTUINTPTR Value;
206 int rc = pfnGetImport(&pModElf->Core, "", pszName, ~0, &Value, pvUser);
207 if (RT_FAILURE(rc))
208 {
209 AssertMsgFailed(("Failed to resolve '%s' rc=%Rrc\n", pszName, rc));
210 return rc;
211 }
212 *pSymValue = (Elf_Addr)Value;
213 if ((RTUINTPTR)*pSymValue != Value)
214 {
215 AssertMsgFailed(("Symbol value overflowed! '%s'\n", pszName));
216 return VERR_SYMBOL_VALUE_TOO_BIG;
217 }
218
219 Log2(("rtldrELF: #%-3d - UNDEF " FMT_ELF_ADDR " '%s'\n", iSym, *pSymValue, pszName));
220 break;
221 }
222
223 /*
224 * Absolute symbols needs no fixing since they are, well, absolute.
225 */
226 case SHN_ABS:
227 *pSymValue = pSym->st_value;
228 Log2(("rtldrELF: #%-3d - ABS " FMT_ELF_ADDR " '%s'\n", iSym, *pSymValue, pszName));
229 break;
230
231 /*
232 * All other symbols are adressed relative to their section and need to be fixed up.
233 */
234 default:
235 if (pSym->st_shndx >= pModElf->Ehdr.e_shnum)
236 {
237 /* what about common symbols? */
238 AssertMsg(pSym->st_shndx < pModElf->Ehdr.e_shnum,
239 ("iSym=%d st_shndx=%d e_shnum=%d pszName=%s\n", iSym, pSym->st_shndx, pModElf->Ehdr.e_shnum, pszName));
240 return VERR_BAD_EXE_FORMAT;
241 }
242 *pSymValue = pSym->st_value + pModElf->paShdrs[pSym->st_shndx].sh_addr + BaseAddr;
243 Log2(("rtldrELF: #%-3d - %5d " FMT_ELF_ADDR " '%s'\n", iSym, pSym->st_shndx, *pSymValue, pszName));
244 break;
245 }
246
247 return VINF_SUCCESS;
248}
249
250
251/**
252 * Applies the fixups for a sections.
253 *
254 * @returns iprt status code.
255 * @param pModElf The ELF loader module instance data.
256 * @param BaseAddr The base address which the module is being fixedup to.
257 * @param pfnGetImport The callback function to use to resolve imports (aka unresolved externals).
258 * @param pvUser User argument to pass to the callback.
259 * @param SecAddr The section address. This is the address the relocations are relative to.
260 * @param cbSec The section size. The relocations must be inside this.
261 * @param pu8SecBaseR Where we read section bits from.
262 * @param pu8SecBaseW Where we write section bits to.
263 * @param pvRelocs Pointer to where we read the relocations from.
264 * @param cbRelocs Size of the relocations.
265 */
266static int RTLDRELF_NAME(RelocateSection)(PRTLDRMODELF pModElf, Elf_Addr BaseAddr, PFNRTLDRIMPORT pfnGetImport, void *pvUser,
267 const Elf_Addr SecAddr, Elf_Size cbSec, const uint8_t *pu8SecBaseR, uint8_t *pu8SecBaseW,
268 const void *pvRelocs, Elf_Size cbRelocs)
269{
270 /*
271 * Iterate the relocations.
272 * The relocations are stored in an array of Elf32_Rel records and covers the entire relocation section.
273 */
274 const Elf_Reloc *paRels = (const Elf_Reloc *)pvRelocs;
275 const unsigned iRelMax = (unsigned)(cbRelocs / sizeof(paRels[0]));
276 AssertMsgReturn(iRelMax == cbRelocs / sizeof(paRels[0]), (FMT_ELF_SIZE "\n", cbRelocs / sizeof(paRels[0])), VERR_IMAGE_TOO_BIG);
277 for (unsigned iRel = 0; iRel < iRelMax; iRel++)
278 {
279 /*
280 * Get the symbol.
281 */
282 const Elf_Sym *pSym;
283 Elf_Addr SymValue = 0; /* shut up gcc-4 */
284 int rc = RTLDRELF_NAME(Symbol)(pModElf, BaseAddr, pfnGetImport, pvUser, ELF_R_SYM(paRels[iRel].r_info), &pSym, &SymValue);
285 if (RT_FAILURE(rc))
286 return rc;
287
288 Log3(("rtldrELF: " FMT_ELF_ADDR " %02x %06x - " FMT_ELF_ADDR " %3d %02x %s\n",
289 paRels[iRel].r_offset, ELF_R_TYPE(paRels[iRel].r_info), (unsigned)ELF_R_SYM(paRels[iRel].r_info),
290 SymValue, (unsigned)pSym->st_shndx, pSym->st_info, ELF_STR(pModElf, pSym->st_name)));
291
292 /*
293 * Apply the fixup.
294 */
295 AssertMsgReturn(paRels[iRel].r_offset < cbSec, (FMT_ELF_ADDR " " FMT_ELF_SIZE "\n", paRels[iRel].r_offset, cbSec), VERR_LDRELF_INVALID_RELOCATION_OFFSET);
296#if ELF_MODE == 32
297 const Elf_Addr *pAddrR = (const Elf_Addr *)(pu8SecBaseR + paRels[iRel].r_offset); /* Where to read the addend. */
298#endif
299 Elf_Addr *pAddrW = (Elf_Addr *)(pu8SecBaseW + paRels[iRel].r_offset); /* Where to write the fixup. */
300 switch (ELF_R_TYPE(paRels[iRel].r_info))
301 {
302#if ELF_MODE == 32
303 /*
304 * Absolute addressing.
305 */
306 case R_386_32:
307 {
308 const Elf_Addr Value = SymValue + *pAddrR;
309 *(uint32_t *)pAddrW = Value;
310 Log4((FMT_ELF_ADDR": R_386_32 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n",
311 SecAddr + paRels[iRel].r_offset + BaseAddr, Value, SymValue));
312 break;
313 }
314
315 /*
316 * PC relative addressing.
317 */
318 case R_386_PC32:
319 {
320 const Elf_Addr SourceAddr = SecAddr + paRels[iRel].r_offset + BaseAddr; /* Where the source really is. */
321 const Elf_Addr Value = SymValue + *(uint32_t *)pAddrR - SourceAddr;
322 *(uint32_t *)pAddrW = Value;
323 Log4((FMT_ELF_ADDR": R_386_PC32 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n",
324 SourceAddr, Value, SymValue));
325 break;
326 }
327
328 /* ignore */
329 case R_386_NONE:
330 break;
331
332#elif ELF_MODE == 64
333
334 /*
335 * Absolute addressing
336 */
337 case R_X86_64_64:
338 {
339 const Elf_Addr Value = SymValue + paRels[iRel].r_addend;
340 *(uint64_t *)pAddrW = Value;
341 Log4((FMT_ELF_ADDR": R_X86_64_64 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n",
342 SecAddr + paRels[iRel].r_offset + BaseAddr, Value, SymValue));
343 break;
344 }
345
346 /*
347 * Trunacated 32-bit value (zero-extendedable to the 64-bit value).
348 */
349 case R_X86_64_32:
350 {
351 const Elf_Addr Value = SymValue + paRels[iRel].r_addend;
352 *(uint32_t *)pAddrW = (uint32_t)Value;
353 Log4((FMT_ELF_ADDR": R_X86_64_32 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n",
354 SecAddr + paRels[iRel].r_offset + BaseAddr, Value, SymValue));
355 AssertMsgReturn((Elf_Addr)*(uint32_t *)pAddrW == Value, ("Value=" FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG);
356 break;
357 }
358
359 /*
360 * Truncated 32-bit value (sign-extendedable to the 64-bit value).
361 */
362 case R_X86_64_32S:
363 {
364 const Elf_Addr Value = SymValue + paRels[iRel].r_addend;
365 *(int32_t *)pAddrW = (int32_t)Value;
366 Log4((FMT_ELF_ADDR": R_X86_64_32S Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n",
367 SecAddr + paRels[iRel].r_offset + BaseAddr, Value, SymValue));
368 AssertMsgReturn((Elf_Addr)*(int32_t *)pAddrW == Value, ("Value=" FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG); /** @todo check the sign-extending here. */
369 break;
370 }
371
372 /*
373 * PC relative addressing.
374 */
375 case R_X86_64_PC32:
376 {
377 const Elf_Addr SourceAddr = SecAddr + paRels[iRel].r_offset + BaseAddr; /* Where the source really is. */
378 const Elf_Addr Value = SymValue + paRels[iRel].r_addend - SourceAddr;
379 *(int32_t *)pAddrW = (int32_t)Value;
380 Log4((FMT_ELF_ADDR": R_X86_64_PC32 Value=" FMT_ELF_ADDR " SymValue=" FMT_ELF_ADDR "\n",
381 SourceAddr, Value, SymValue));
382 AssertMsgReturn((Elf_Addr)*(int32_t *)pAddrW == Value, ("Value=" FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG); /** @todo check the sign-extending here. */
383 break;
384 }
385
386 /* ignore */
387 case R_X86_64_NONE:
388 break;
389#endif
390
391 default:
392 AssertMsgFailed(("Unknown relocation type: %d (iRel=%d iRelMax=%d)\n",
393 ELF_R_TYPE(paRels[iRel].r_info), iRel, iRelMax));
394 return VERR_LDRELF_RELOCATION_NOT_SUPPORTED;
395 }
396 }
397
398 return VINF_SUCCESS;
399}
400
401
402
403/** @copydoc RTLDROPS::pfnClose */
404static DECLCALLBACK(int) RTLDRELF_NAME(Close)(PRTLDRMODINTERNAL pMod)
405{
406 PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
407
408 if (pModElf->paShdrs)
409 {
410 RTMemFree(pModElf->paShdrs);
411 pModElf->paShdrs = NULL;
412 }
413
414 if (pModElf->pReader)
415 {
416 pModElf->pReader->pfnDestroy(pModElf->pReader);
417 pModElf->pReader = NULL;
418 }
419
420 pModElf->pvBits = NULL;
421
422 return VINF_SUCCESS;
423}
424
425
426/** @copydoc RTLDROPS::Done */
427static DECLCALLBACK(int) RTLDRELF_NAME(Done)(PRTLDRMODINTERNAL pMod)
428{
429 //PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
430 /** @todo Have to think more about this .... */
431 return -1;
432}
433
434
435/** @copydoc RTLDROPS::EnumSymbols */
436static DECLCALLBACK(int) RTLDRELF_NAME(EnumSymbols)(PRTLDRMODINTERNAL pMod, unsigned fFlags, const void *pvBits, RTUINTPTR BaseAddress,
437 PFNRTLDRENUMSYMS pfnCallback, void *pvUser)
438{
439 PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
440
441 /*
442 * Validate the input.
443 */
444 Elf_Addr BaseAddr = (Elf_Addr)BaseAddress;
445 AssertMsgReturn((RTUINTPTR)BaseAddr == BaseAddress, ("#RTptr", BaseAddress), VERR_IMAGE_BASE_TOO_HIGH);
446
447 /*
448 * Make sure we've got the string and symbol tables. (We don't need the pvBits.)
449 */
450 int rc = RTLDRELF_NAME(MapBits)(pModElf, false);
451 if (RT_FAILURE(rc))
452 return rc;
453
454 /*
455 * Enumerate the symbol table.
456 */
457 const Elf_Sym *paSyms = pModElf->paSyms;
458 unsigned cSyms = pModElf->cSyms;
459 for (unsigned iSym = 1; iSym < cSyms; iSym++)
460 {
461 /*
462 * Skip imports (undefined).
463 */
464 if (paSyms[iSym].st_shndx != SHN_UNDEF)
465 {
466 /*
467 * Calc value and get name.
468 */
469 Elf_Addr Value;
470 if (paSyms[iSym].st_shndx == SHN_ABS)
471 /* absolute symbols are not subject to any relocation. */
472 Value = paSyms[iSym].st_value;
473 else if (paSyms[iSym].st_shndx < pModElf->Ehdr.e_shnum)
474 /* relative to the section. */
475 Value = BaseAddr + paSyms[iSym].st_value + pModElf->paShdrs[paSyms[iSym].st_shndx].sh_addr;
476 else
477 {
478 AssertMsgFailed(("Arg! paSyms[%u].st_shndx=" FMT_ELF_HALF "\n", iSym, paSyms[iSym].st_shndx));
479 return VERR_BAD_EXE_FORMAT;
480 }
481 const char *pszName = ELF_STR(pModElf, paSyms[iSym].st_name);
482 if ( (pszName && *pszName)
483 && ( (fFlags & RTLDR_ENUM_SYMBOL_FLAGS_ALL)
484 || ELF_ST_BIND(paSyms[iSym].st_info) == STB_GLOBAL)
485 )
486 {
487 /*
488 * Call back.
489 */
490 AssertMsgReturn(Value == (RTUINTPTR)Value, (FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG);
491 rc = pfnCallback(pMod, pszName, ~0, (RTUINTPTR)Value, pvUser);
492 if (rc)
493 return rc;
494 }
495 }
496 }
497
498 return VINF_SUCCESS;
499}
500
501
502/** @copydoc RTLDROPS::GetImageSize */
503static DECLCALLBACK(size_t) RTLDRELF_NAME(GetImageSize)(PRTLDRMODINTERNAL pMod)
504{
505 PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
506
507 return pModElf->cbImage;
508}
509
510
511/** @copydoc RTLDROPS::GetBits */
512static DECLCALLBACK(int) RTLDRELF_NAME(GetBits)(PRTLDRMODINTERNAL pMod, void *pvBits, RTUINTPTR BaseAddress, PFNRTLDRIMPORT pfnGetImport, void *pvUser)
513{
514 PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
515
516 /*
517 * Load the bits into pvBits.
518 */
519 const Elf_Shdr *paShdrs = pModElf->paShdrs;
520 for (unsigned iShdr = 0; iShdr < pModElf->Ehdr.e_shnum; iShdr++)
521 {
522 if (paShdrs[iShdr].sh_flags & SHF_ALLOC)
523 {
524 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);
525 switch (paShdrs[iShdr].sh_type)
526 {
527 case SHT_NOBITS:
528 memset((uint8_t *)pvBits + paShdrs[iShdr].sh_addr, 0, (size_t)paShdrs[iShdr].sh_size);
529 break;
530
531 case SHT_PROGBITS:
532 default:
533 {
534 int rc = pModElf->pReader->pfnRead(pModElf->pReader, (uint8_t *)pvBits + paShdrs[iShdr].sh_addr,
535 (size_t)paShdrs[iShdr].sh_size, paShdrs[iShdr].sh_offset);
536 if (RT_FAILURE(rc))
537 {
538 Log(("RTLdrELF: %s: Read error when reading " FMT_ELF_SIZE " bytes at " FMT_ELF_OFF ", iShdr=%d\n",
539 pModElf->pReader->pfnLogName(pModElf->pReader),
540 paShdrs[iShdr].sh_size, paShdrs[iShdr].sh_offset, iShdr));
541 return rc;
542 }
543 }
544 }
545 }
546 }
547
548 /*
549 * Relocate the image.
550 */
551 return pModElf->Core.pOps->pfnRelocate(pMod, pvBits, BaseAddress, ~(RTUINTPTR)0, pfnGetImport, pvUser);
552}
553
554
555/** @copydoc RTLDROPS::Relocate */
556static DECLCALLBACK(int) RTLDRELF_NAME(Relocate)(PRTLDRMODINTERNAL pMod, void *pvBits, RTUINTPTR NewBaseAddress, RTUINTPTR OldBaseAddress, PFNRTLDRIMPORT pfnGetImport, void *pvUser)
557{
558 PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
559
560 /*
561 * Validate the input.
562 */
563 Elf_Addr BaseAddr = (Elf_Addr)NewBaseAddress;
564 AssertMsgReturn((RTUINTPTR)BaseAddr == NewBaseAddress, ("#RTptr", NewBaseAddress), VERR_IMAGE_BASE_TOO_HIGH);
565
566 /*
567 * Map the image bits if not already done and setup pointer into it.
568 */
569 int rc = RTLDRELF_NAME(MapBits)(pModElf, true);
570 if (RT_FAILURE(rc))
571 return rc;
572
573 /*
574 * Iterate the sections looking for interesting SHT_REL[A] sections.
575 * SHT_REL[A] sections have the section index of the section they contain fixups
576 * for in the sh_info member.
577 */
578 const Elf_Shdr *paShdrs = pModElf->paShdrs;
579#ifdef LOG_ENABLED
580 const char *pszLogName = pModElf->pReader->pfnLogName(pModElf->pReader);
581 Log2(("rtLdrElf: %s: Fixing up image\n", pszLogName));
582#endif
583 for (unsigned iShdr = 0; iShdr < pModElf->Ehdr.e_shnum; iShdr++)
584 {
585 const Elf_Shdr *pShdrRel = &paShdrs[iShdr];
586
587 /*
588 * Skip sections without interest to us.
589 */
590#if ELF_MODE == 32
591 if (pShdrRel->sh_type != SHT_REL)
592#else
593 if (pShdrRel->sh_type != SHT_RELA)
594#endif
595 continue;
596 if (pShdrRel->sh_info >= pModElf->Ehdr.e_shnum)
597 continue;
598 const Elf_Shdr *pShdr = &paShdrs[pShdrRel->sh_info]; /* the section to fixup. */
599 if (!(pShdr->sh_flags & SHF_ALLOC))
600 continue;
601
602 /*
603 * Relocate the section.
604 */
605 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",
606 pszLogName, (int)pShdrRel->sh_info, ELF_STR(pModElf, pShdr->sh_name), (int)pShdr->sh_info, (int)pShdr->sh_link,
607 iShdr, ELF_STR(pModElf, pShdrRel->sh_name), (int)pShdrRel->sh_info, (int)pShdrRel->sh_link));
608
609 /** @todo Make RelocateSection a function pointer so we can select the one corresponding to the machine when opening the image. */
610 rc = RTLDRELF_NAME(RelocateSection)(pModElf, BaseAddr, pfnGetImport, pvUser,
611 pShdr->sh_addr,
612 pShdr->sh_size,
613 (const uint8_t *)pModElf->pvBits + pShdr->sh_offset,
614 (uint8_t *)pvBits + pShdr->sh_addr,
615 (const uint8_t *)pModElf->pvBits + pShdrRel->sh_offset,
616 pShdrRel->sh_size);
617 if (RT_FAILURE(rc))
618 return rc;
619 }
620 return VINF_SUCCESS;
621}
622
623
624/** @copydoc RTLDROPS::pfnGetSymbolEx */
625static DECLCALLBACK(int) RTLDRELF_NAME(GetSymbolEx)(PRTLDRMODINTERNAL pMod, const void *pvBits, RTUINTPTR BaseAddress, const char *pszSymbol, RTUINTPTR *pValue)
626{
627 PRTLDRMODELF pModElf = (PRTLDRMODELF)pMod;
628 NOREF(pvBits);
629
630 /*
631 * Validate the input.
632 */
633 Elf_Addr BaseAddr = (Elf_Addr)BaseAddress;
634 AssertMsgReturn((RTUINTPTR)BaseAddr == BaseAddress, ("#RTptr", BaseAddress), VERR_IMAGE_BASE_TOO_HIGH);
635
636 /*
637 * Map the image bits if not already done and setup pointer into it.
638 */
639 int rc = RTLDRELF_NAME(MapBits)(pModElf, true);
640 if (RT_FAILURE(rc))
641 return rc;
642
643 /*
644 * Calc all kinds of pointers before we start iterating the symbol table.
645 */
646 const char *pStr = pModElf->pStr;
647 const Elf_Sym *paSyms = pModElf->paSyms;
648 unsigned cSyms = pModElf->cSyms;
649 for (unsigned iSym = 1; iSym < cSyms; iSym++)
650 {
651 /* Undefined symbols are not exports, they are imports. */
652 if ( paSyms[iSym].st_shndx != SHN_UNDEF
653 && ( ELF_ST_BIND(paSyms[iSym].st_info) == STB_GLOBAL
654 || ELF_ST_BIND(paSyms[iSym].st_info) == STB_WEAK))
655 {
656 /* Validate the name string and try match with it. */
657 if (paSyms[iSym].st_name < pModElf->cbStr)
658 {
659 if (!strcmp(pszSymbol, pStr + paSyms[iSym].st_name))
660 {
661 /* matched! */
662 Elf_Addr Value;
663 if (paSyms[iSym].st_shndx == SHN_ABS)
664 /* absolute symbols are not subject to any relocation. */
665 Value = paSyms[iSym].st_value;
666 else if (paSyms[iSym].st_shndx < pModElf->Ehdr.e_shnum)
667 /* relative to the section. */
668 Value = BaseAddr + paSyms[iSym].st_value + pModElf->paShdrs[paSyms[iSym].st_shndx].sh_addr;
669 else
670 {
671 AssertMsgFailed(("Arg. paSyms[iSym].st_shndx=%d\n", paSyms[iSym].st_shndx));
672 return VERR_BAD_EXE_FORMAT;
673 }
674 AssertMsgReturn(Value == (RTUINTPTR)Value, (FMT_ELF_ADDR "\n", Value), VERR_SYMBOL_VALUE_TOO_BIG);
675 *pValue = (RTUINTPTR)Value;
676 return VINF_SUCCESS;
677 }
678 }
679 else
680 {
681 AssertMsgFailed(("String outside string table! iSym=%d paSyms[iSym].st_name=%#x\n", iSym, paSyms[iSym].st_name));
682 return VERR_LDRELF_INVALID_SYMBOL_NAME_OFFSET;
683 }
684 }
685 }
686
687 return VERR_SYMBOL_NOT_FOUND;
688}
689
690
691
692/**
693 * The ELF module operations.
694 */
695static RTLDROPS RTLDRELF_MID(s_rtldrElf,Ops) =
696{
697#if ELF_MODE == 32
698 "elf32",
699#elif ELF_MODE == 64
700 "elf64",
701#endif
702 RTLDRELF_NAME(Close),
703 NULL, /* Get Symbol */
704 RTLDRELF_NAME(Done),
705 RTLDRELF_NAME(EnumSymbols),
706 /* ext: */
707 RTLDRELF_NAME(GetImageSize),
708 RTLDRELF_NAME(GetBits),
709 RTLDRELF_NAME(Relocate),
710 RTLDRELF_NAME(GetSymbolEx),
711 0
712};
713
714
715
716/**
717 * Validates the ELF header.
718 *
719 * @returns iprt status code.
720 * @param pEhdr Pointer to the ELF header.
721 * @param pszLogName The log name.
722 * @param cbRawImage The size of the raw image.
723 */
724static int RTLDRELF_NAME(ValidateElfHeader)(const Elf_Ehdr *pEhdr, const char *pszLogName, uint64_t cbRawImage, PRTLDRARCH penmArch)
725{
726 Log3(("RTLdrELF: e_ident: %.*Rhxs\n"
727 "RTLdrELF: e_type: " FMT_ELF_HALF "\n"
728 "RTLdrELF: e_version: " FMT_ELF_HALF "\n"
729 "RTLdrELF: e_entry: " FMT_ELF_ADDR "\n"
730 "RTLdrELF: e_phoff: " FMT_ELF_OFF "\n"
731 "RTLdrELF: e_shoff: " FMT_ELF_OFF "\n"
732 "RTLdrELF: e_flags: " FMT_ELF_WORD "\n"
733 "RTLdrELF: e_ehsize: " FMT_ELF_HALF "\n"
734 "RTLdrELF: e_phentsize: " FMT_ELF_HALF "\n"
735 "RTLdrELF: e_phnum: " FMT_ELF_HALF "\n"
736 "RTLdrELF: e_shentsize: " FMT_ELF_HALF "\n"
737 "RTLdrELF: e_shnum: " FMT_ELF_HALF "\n"
738 "RTLdrELF: e_shstrndx: " FMT_ELF_HALF "\n",
739 RT_ELEMENTS(pEhdr->e_ident), &pEhdr->e_ident[0], pEhdr->e_type, pEhdr->e_version,
740 pEhdr->e_entry, pEhdr->e_phoff, pEhdr->e_shoff,pEhdr->e_flags, pEhdr->e_ehsize, pEhdr->e_phentsize,
741 pEhdr->e_phnum, pEhdr->e_shentsize, pEhdr->e_shnum, pEhdr->e_shstrndx));
742
743 if ( pEhdr->e_ident[EI_MAG0] != ELFMAG0
744 || pEhdr->e_ident[EI_MAG1] != ELFMAG1
745 || pEhdr->e_ident[EI_MAG2] != ELFMAG2
746 || pEhdr->e_ident[EI_MAG3] != ELFMAG3
747 )
748 {
749 Log(("RTLdrELF: %s: Invalid ELF magic (%.*Rhxs)\n", pszLogName, sizeof(pEhdr->e_ident), pEhdr->e_ident));
750 return VERR_BAD_EXE_FORMAT;
751 }
752 if (pEhdr->e_ident[EI_CLASS] != RTLDRELF_SUFF(ELFCLASS))
753 {
754 Log(("RTLdrELF: %s: Invalid ELF class (%.*Rhxs)\n", pszLogName, sizeof(pEhdr->e_ident), pEhdr->e_ident));
755 return VERR_BAD_EXE_FORMAT;
756 }
757 if (pEhdr->e_ident[EI_DATA] != ELFDATA2LSB)
758 {
759 Log(("RTLdrELF: %s: ELF endian %x is unsupported\n", pEhdr->e_ident[EI_DATA]));
760 return VERR_LDRELF_ODD_ENDIAN;
761 }
762 if (pEhdr->e_version != EV_CURRENT)
763 {
764 Log(("RTLdrELF: %s: ELF version %x is unsupported\n", pEhdr->e_version));
765 return VERR_LDRELF_VERSION;
766 }
767
768 if (sizeof(Elf_Ehdr) != pEhdr->e_ehsize)
769 {
770 Log(("RTLdrELF: %s: Elf header e_ehsize is %d expected %d!\n",
771 pszLogName, pEhdr->e_ehsize, sizeof(Elf_Ehdr)));
772 return VERR_BAD_EXE_FORMAT;
773 }
774 if ( sizeof(Elf_Phdr) != pEhdr->e_phentsize
775 && ( pEhdr->e_phnum != 0
776 || pEhdr->e_type == ET_DYN))
777 {
778 Log(("RTLdrELF: %s: Elf header e_phentsize is %d expected %d!\n",
779 pszLogName, pEhdr->e_phentsize, sizeof(Elf_Phdr)));
780 return VERR_BAD_EXE_FORMAT;
781 }
782 if (sizeof(Elf_Shdr) != pEhdr->e_shentsize)
783 {
784 Log(("RTLdrELF: %s: Elf header e_shentsize is %d expected %d!\n",
785 pszLogName, pEhdr->e_shentsize, sizeof(Elf_Shdr)));
786 return VERR_BAD_EXE_FORMAT;
787 }
788
789 switch (pEhdr->e_type)
790 {
791 case ET_REL:
792 break;
793 case ET_EXEC:
794 Log(("RTLdrELF: %s: Executable images are not supported yet!\n", pszLogName));
795 return VERR_LDRELF_EXEC;
796 case ET_DYN:
797 Log(("RTLdrELF: %s: Dynamic images are not supported yet!\n", pszLogName));
798 return VERR_LDRELF_DYN;
799 default:
800 Log(("RTLdrELF: %s: image type %#x is not supported!\n", pszLogName, pEhdr->e_type));
801 return VERR_BAD_EXE_FORMAT;
802 }
803
804 switch (pEhdr->e_machine)
805 {
806#if ELF_MODE == 32
807 case EM_386:
808 case EM_486:
809 *penmArch = RTLDRARCH_X86_32;
810 break;
811#elif ELF_MODE == 64
812 case EM_X86_64:
813 *penmArch = RTLDRARCH_AMD64;
814 break;
815#endif
816 default:
817 Log(("RTLdrELF: %s: machine type %u is not supported!\n", pEhdr->e_machine));
818 return VERR_LDRELF_MACHINE;
819 }
820
821 if ( pEhdr->e_phoff < pEhdr->e_ehsize
822 && !(pEhdr->e_phoff && pEhdr->e_phnum)
823 && pEhdr->e_phnum)
824 {
825 Log(("RTLdrELF: %s: The program headers overlap with the ELF header! e_phoff=" FMT_ELF_OFF "\n",
826 pszLogName, pEhdr->e_phoff));
827 return VERR_BAD_EXE_FORMAT;
828 }
829 if ( pEhdr->e_phoff + pEhdr->e_phnum * pEhdr->e_phentsize > cbRawImage
830 || pEhdr->e_phoff + pEhdr->e_phnum * pEhdr->e_phentsize < pEhdr->e_phoff)
831 {
832 Log(("RTLdrELF: %s: The program headers extends beyond the file! e_phoff=" FMT_ELF_OFF " e_phnum=" FMT_ELF_HALF "\n",
833 pszLogName, pEhdr->e_phoff, pEhdr->e_phnum));
834 return VERR_BAD_EXE_FORMAT;
835 }
836
837
838 if ( pEhdr->e_shoff < pEhdr->e_ehsize
839 && !(pEhdr->e_shoff && pEhdr->e_shnum))
840 {
841 Log(("RTLdrELF: %s: The section headers overlap with the ELF header! e_shoff=" FMT_ELF_OFF "\n",
842 pszLogName, pEhdr->e_shoff));
843 return VERR_BAD_EXE_FORMAT;
844 }
845 if ( pEhdr->e_shoff + pEhdr->e_shnum * pEhdr->e_shentsize > cbRawImage
846 || pEhdr->e_shoff + pEhdr->e_shnum * pEhdr->e_shentsize < pEhdr->e_shoff)
847 {
848 Log(("RTLdrELF: %s: The section headers extends beyond the file! e_shoff=" FMT_ELF_OFF " e_shnum=" FMT_ELF_HALF "\n",
849 pszLogName, pEhdr->e_shoff, pEhdr->e_shnum));
850 return VERR_BAD_EXE_FORMAT;
851 }
852
853 return VINF_SUCCESS;
854}
855
856/**
857 * Gets the section header name.
858 *
859 * @returns pszName.
860 * @param pReader The loader reader instance.
861 * @param pEhdr The elf header.
862 * @param offName The offset of the section header name.
863 * @param pszName Where to store the name.
864 * @param cbName The size of the buffer pointed to by pszName.
865 */
866const char *RTLDRELF_NAME(GetSHdrName)(PRTLDRMODELF pModElf, Elf_Word offName, char *pszName, size_t cbName)
867{
868 RTFOFF off = pModElf->paShdrs[pModElf->Ehdr.e_shstrndx].sh_offset + offName;
869 int rc = pModElf->pReader->pfnRead(pModElf->pReader, pszName, cbName - 1, off);
870 if (RT_FAILURE(rc))
871 {
872 /* read by for byte. */
873 for (unsigned i = 0; i < cbName; i++, off++)
874 {
875 rc = pModElf->pReader->pfnRead(pModElf->pReader, pszName + i, 1, off);
876 if (RT_FAILURE(rc))
877 {
878 pszName[i] = '\0';
879 break;
880 }
881 }
882 }
883
884 pszName[cbName - 1] = '\0';
885 return pszName;
886}
887
888
889/**
890 * Validates a section header.
891 *
892 * @returns iprt status code.
893 * @param pModElf Pointer to the module structure.
894 * @param iShdr The index of section header which should be validated.
895 * The section headers are found in the pModElf->paShdrs array.
896 * @param pszLogName The log name.
897 * @param cbRawImage The size of the raw image.
898 */
899static int RTLDRELF_NAME(ValidateSectionHeader)(PRTLDRMODELF pModElf, unsigned iShdr, const char *pszLogName, RTFOFF cbRawImage)
900{
901 const Elf_Shdr *pShdr = &pModElf->paShdrs[iShdr];
902 char szSectionName[80]; NOREF(szSectionName);
903 Log3(("RTLdrELF: Section Header #%d:\n"
904 "RTLdrELF: sh_name: " FMT_ELF_WORD " - %s\n"
905 "RTLdrELF: sh_type: " FMT_ELF_WORD " (%s)\n"
906 "RTLdrELF: sh_flags: " FMT_ELF_XWORD "\n"
907 "RTLdrELF: sh_addr: " FMT_ELF_ADDR "\n"
908 "RTLdrELF: sh_offset: " FMT_ELF_OFF "\n"
909 "RTLdrELF: sh_size: " FMT_ELF_XWORD "\n"
910 "RTLdrELF: sh_link: " FMT_ELF_WORD "\n"
911 "RTLdrELF: sh_info: " FMT_ELF_WORD "\n"
912 "RTLdrELF: sh_addralign: " FMT_ELF_XWORD "\n"
913 "RTLdrELF: sh_entsize: " FMT_ELF_XWORD "\n",
914 iShdr,
915 pShdr->sh_name, RTLDRELF_NAME(GetSHdrName)(pModElf, pShdr->sh_name, szSectionName, sizeof(szSectionName)),
916 pShdr->sh_type, rtldrElfGetShdrType(pShdr->sh_type), pShdr->sh_flags, pShdr->sh_addr,
917 pShdr->sh_offset, pShdr->sh_size, pShdr->sh_link, pShdr->sh_info, pShdr->sh_addralign,
918 pShdr->sh_entsize));
919
920 if (pShdr->sh_link >= pModElf->Ehdr.e_shnum)
921 {
922 Log(("RTLdrELF: %s: Shdr #%d: sh_link (%d) is beyond the end of the section table (%d)!\n",
923 pszLogName, iShdr, pShdr->sh_link, pModElf->Ehdr.e_shnum));
924 return VERR_BAD_EXE_FORMAT;
925 }
926
927 switch (pShdr->sh_type)
928 {
929 /** @todo find specs and check up which sh_info fields indicates section table entries */
930 case 12301230:
931 if (pShdr->sh_info >= pModElf->Ehdr.e_shnum)
932 {
933 Log(("RTLdrELF: %s: Shdr #%d: sh_info (%d) is beyond the end of the section table (%d)!\n",
934 pszLogName, iShdr, pShdr->sh_link, pModElf->Ehdr.e_shnum));
935 return VERR_BAD_EXE_FORMAT;
936 }
937 break;
938
939 case SHT_NULL:
940 case SHT_PROGBITS:
941 case SHT_SYMTAB:
942 case SHT_STRTAB:
943 case SHT_RELA:
944 case SHT_HASH:
945 case SHT_DYNAMIC:
946 case SHT_NOTE:
947 case SHT_NOBITS:
948 case SHT_REL:
949 case SHT_SHLIB:
950 case SHT_DYNSYM:
951 /*
952 * For these types sh_info doesn't have any special meaning, or anything which
953 * we need/can validate now.
954 */
955 break;
956
957
958 default:
959 Log(("RTLdrELF: %s: Warning, unknown type %d!\n", pszLogName, pShdr->sh_type));
960 break;
961 }
962
963 if ( pShdr->sh_type != SHT_NOBITS
964 && pShdr->sh_size)
965 {
966 RTFOFF offEnd = pShdr->sh_offset + pShdr->sh_size;
967 if ( offEnd > cbRawImage
968 || offEnd < (RTFOFF)pShdr->sh_offset)
969 {
970 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",
971 pszLogName, iShdr, pShdr->sh_offset, pShdr->sh_size, offEnd, cbRawImage));
972 return VERR_BAD_EXE_FORMAT;
973 }
974 if (pShdr->sh_offset < sizeof(Elf_Ehdr))
975 {
976 Log(("RTLdrELF: %s: Shdr #%d: sh_offset (" FMT_ELF_OFF ") + sh_size (" FMT_ELF_XWORD ") is starting in the ELF header!\n",
977 pszLogName, iShdr, pShdr->sh_offset, pShdr->sh_size, cbRawImage));
978 return VERR_BAD_EXE_FORMAT;
979 }
980 }
981
982 return VINF_SUCCESS;
983}
984
985
986
987/**
988 * Opens an ELF image, fixed bitness.
989 *
990 * @returns iprt status code.
991 * @param pReader The loader reader instance which will provide the raw image bits.
992 * @param fFlags Reserved, MBZ.
993 * @param enmArch Architecture specifier.
994 * @param phLdrMod Where to store the handle.
995 */
996static int RTLDRELF_NAME(Open)(PRTLDRREADER pReader, uint32_t fFlags, RTLDRARCH enmArch, PRTLDRMOD phLdrMod)
997{
998 const char *pszLogName = pReader->pfnLogName(pReader);
999 RTFOFF cbRawImage = pReader->pfnSize(pReader);
1000
1001 /*
1002 * Create the loader module instance.
1003 */
1004 PRTLDRMODELF pModElf = (PRTLDRMODELF)RTMemAllocZ(sizeof(*pModElf));
1005 if (!pModElf)
1006 return VERR_NO_MEMORY;
1007
1008 pModElf->Core.u32Magic = RTLDRMOD_MAGIC;
1009 pModElf->Core.eState = LDR_STATE_INVALID;
1010 pModElf->pReader = pReader;
1011 //pModElf->pvBits = NULL;
1012 //pModElf->Ehdr = {0};
1013 //pModElf->paShdrs = NULL;
1014 //pModElf->paSyms = NULL;
1015 pModElf->iSymSh = ~0U;
1016 pModElf->cSyms = 0;
1017 pModElf->iStrSh = ~0U;
1018 pModElf->cbStr = 0;
1019 pModElf->cbImage = 0;
1020 //pModElf->pStr = NULL;
1021
1022 /*
1023 * Read and validate the ELF header and match up the CPU architecture.
1024 */
1025 int rc = pReader->pfnRead(pReader, &pModElf->Ehdr, sizeof(pModElf->Ehdr), 0);
1026 if (RT_SUCCESS(rc))
1027 {
1028 RTLDRARCH enmArchImage = RTLDRARCH_INVALID; /* shut up gcc */
1029 rc = RTLDRELF_NAME(ValidateElfHeader)(&pModElf->Ehdr, pszLogName, cbRawImage, &enmArchImage);
1030 if (RT_SUCCESS(rc))
1031 {
1032 if ( enmArch != RTLDRARCH_WHATEVER
1033 && enmArch != enmArchImage)
1034 rc = VERR_LDR_ARCH_MISMATCH;
1035 }
1036 }
1037 if (RT_SUCCESS(rc))
1038 {
1039 /*
1040 * Read the section headers.
1041 */
1042 Elf_Shdr *paShdrs = (Elf_Shdr *)RTMemAlloc(pModElf->Ehdr.e_shnum * sizeof(Elf_Shdr));
1043 if (paShdrs)
1044 {
1045 pModElf->paShdrs = paShdrs;
1046 rc = pReader->pfnRead(pReader, paShdrs, pModElf->Ehdr.e_shnum * sizeof(Elf_Shdr),
1047 pModElf->Ehdr.e_shoff);
1048 if (RT_SUCCESS(rc))
1049 {
1050 /*
1051 * Validate the section headers, allocate memory for the sections (determin the image size),
1052 * and find relevant sections.
1053 */
1054 for (unsigned i = 0; i < pModElf->Ehdr.e_shnum; i++)
1055 {
1056 rc = RTLDRELF_NAME(ValidateSectionHeader)(pModElf, i, pszLogName, cbRawImage);
1057 if (RT_FAILURE(rc))
1058 break;
1059
1060 /* Allocate memory addresses for the section. */
1061 if (paShdrs[i].sh_flags & SHF_ALLOC)
1062 {
1063 paShdrs[i].sh_addr = paShdrs[i].sh_addralign
1064 ? RT_ALIGN_T(pModElf->cbImage, paShdrs[i].sh_addralign, Elf_Addr)
1065 : (Elf_Addr)pModElf->cbImage;
1066 pModElf->cbImage = (size_t)paShdrs[i].sh_addr + (size_t)paShdrs[i].sh_size;
1067 AssertMsgReturn(pModElf->cbImage == paShdrs[i].sh_addr + paShdrs[i].sh_size,
1068 (FMT_ELF_ADDR "\n", paShdrs[i].sh_addr + paShdrs[i].sh_size),
1069 VERR_IMAGE_TOO_BIG);
1070 Log2(("RTLdrElf: %s: Assigned " FMT_ELF_ADDR " to section #%d\n", pszLogName, paShdrs[i].sh_addr, i));
1071 }
1072
1073 /* We're looking for symbol tables. */
1074 if (paShdrs[i].sh_type == SHT_SYMTAB)
1075 {
1076 if (pModElf->iSymSh != ~0U)
1077 {
1078 Log(("RTLdrElf: %s: Multiple symbol tabs! iSymSh=%d i=%d\n", pszLogName, pModElf->iSymSh, i));
1079 rc = VERR_LDRELF_MULTIPLE_SYMTABS;
1080 break;
1081 }
1082 pModElf->iSymSh = i;
1083 pModElf->cSyms = (unsigned)(paShdrs[i].sh_size / sizeof(Elf_Sym));
1084 AssertReturn(pModElf->cSyms == paShdrs[i].sh_size / sizeof(Elf_Sym), VERR_IMAGE_TOO_BIG);
1085 pModElf->iStrSh = paShdrs[i].sh_link;
1086 pModElf->cbStr = (unsigned)paShdrs[pModElf->iStrSh].sh_size;
1087 AssertReturn(pModElf->cbStr == paShdrs[pModElf->iStrSh].sh_size, VERR_IMAGE_TOO_BIG);
1088 }
1089 } /* for each section header */
1090
1091 Log2(("RTLdrElf: iSymSh=%u cSyms=%u iStrSh=%u cbStr=%u rc=%Rrc cbImage=%#zx\n",
1092 pModElf->iSymSh, pModElf->cSyms, pModElf->iStrSh, pModElf->cbStr, rc, pModElf->cbImage));
1093
1094 /*
1095 * Are the section headers fine?
1096 * We require there to be symbol & string tables (at least for the time being).
1097 */
1098 if ( pModElf->iSymSh == ~0U
1099 || pModElf->iStrSh == ~0U)
1100 rc = VERR_LDRELF_NO_SYMBOL_OR_NO_STRING_TABS;
1101 if (RT_SUCCESS(rc))
1102 {
1103 pModElf->Core.pOps = &RTLDRELF_MID(s_rtldrElf,Ops);
1104 pModElf->Core.eState = LDR_STATE_OPENED;
1105 *phLdrMod = &pModElf->Core;
1106
1107 LogFlow(("%s: %s: returns VINF_SUCCESS *phLdrMod=%p\n", __FUNCTION__, pszLogName, *phLdrMod));
1108 return VINF_SUCCESS;
1109 }
1110 }
1111
1112 RTMemFree(paShdrs);
1113 }
1114 else
1115 rc = VERR_NO_MEMORY;
1116 }
1117
1118 RTMemFree(pModElf);
1119 LogFlow(("%s: returns %Rrc\n", __FUNCTION__, rc));
1120 return rc;
1121}
1122
1123
1124
1125
1126/*******************************************************************************
1127* Cleanup Constants And Macros *
1128*******************************************************************************/
1129#undef RTLDRELF_NAME
1130#undef RTLDRELF_SUFF
1131#undef RTLDRELF_MID
1132
1133#undef FMT_ELF_ADDR
1134#undef FMT_ELF_HALF
1135#undef FMT_ELF_SHALF
1136#undef FMT_ELF_OFF
1137#undef FMT_ELF_SIZE
1138#undef FMT_ELF_SWORD
1139#undef FMT_ELF_WORD
1140#undef FMT_ELF_XWORD
1141#undef FMT_ELF_SXWORD
1142
1143#undef Elf_Ehdr
1144#undef Elf_Phdr
1145#undef Elf_Shdr
1146#undef Elf_Sym
1147#undef Elf_Rel
1148#undef Elf_Rela
1149#undef Elf_Reloc
1150#undef Elf_Nhdr
1151#undef Elf_Dyn
1152
1153#undef Elf_Addr
1154#undef Elf_Half
1155#undef Elf_Off
1156#undef Elf_Size
1157#undef Elf_Sword
1158#undef Elf_Word
1159
1160#undef RTLDRMODELF
1161#undef PRTLDRMODELF
1162
1163#undef ELF_R_SYM
1164#undef ELF_R_TYPE
1165#undef ELF_R_INFO
1166
1167#undef ELF_ST_BIND
1168
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