2 * Acess2 Dynamic Linker
3 * - By John Hodge (thePowersGang)
6 * - ELF32/ELF64 relocation
8 #ifndef DEBUG // This code is #include'd from the kernel, so DEBUG may already be defined
13 # define PAGE_SIZE 4096
23 # define DEBUGS(v...) SysDebug("ld-acess - " v)
29 # define SUPPORT_ELF64
34 //static const char *csaDT_NAMES[] = {"DT_NULL", "DT_NEEDED", "DT_PLTRELSZ", "DT_PLTGOT", "DT_HASH", "DT_STRTAB", "DT_SYMTAB", "DT_RELA", "DT_RELASZ", "DT_RELAENT", "DT_STRSZ", "DT_SYMENT", "DT_INIT", "DT_FINI", "DT_SONAME", "DT_RPATH", "DT_SYMBOLIC", "DT_REL", "DT_RELSZ", "DT_RELENT", "DT_PLTREL", "DT_DEBUG", "DT_TEXTREL", "DT_JMPREL"};
35 static const char *csaR_NAMES[] = {"R_386_NONE", "R_386_32", "R_386_PC32", "R_386_GOT32", "R_386_PLT32", "R_386_COPY", "R_386_GLOB_DAT", "R_386_JMP_SLOT", "R_386_RELATIVE", "R_386_GOTOFF", "R_386_GOTPC", "R_386_LAST"};
39 void *ElfRelocate(void *Base, char **envp, const char *Filename);
40 int ElfGetSymbol(void *Base, const char *Name, void **Ret, size_t *Size);
41 void *Elf32Relocate(void *Base, char **envp, const char *Filename);
42 int Elf32GetSymbol(void *Base, const char *Name, void **Ret, size_t *Size);
43 int elf_doRelocate_386(uint32_t r_info, uint32_t *ptr, Elf32_Addr addend, int type, int bRela, const char *Sym, intptr_t iBaseDiff);
44 int elf_doRelocate_arm(uint32_t r_info, uint32_t *ptr, Elf32_Addr addend, int type, int bRela, const char *Sym, intptr_t iBaseDiff);
45 int elf_doRelocate_unk(uint32_t , uint32_t *, Elf32_Addr , int , int , const char *, intptr_t);
47 int _Elf64DoReloc_X86_64(void *Base, const char *strtab, Elf64_Sym *symtab, Elf64_Xword r_info, void *ptr, Elf64_Sxword addend);
48 void *Elf64Relocate(void *Base, char **envp, const char *Filename);
49 int Elf64GetSymbol(void *Base, const char *Name, void **Ret, size_t *Size);
51 uint32_t ElfHashString(const char *name);
55 * \fn int ElfRelocate(void *Base, char **envp, const char *Filename)
56 * \brief Relocates a loaded ELF Executable
58 void *ElfRelocate(void *Base, char **envp, const char *Filename)
60 Elf32_Ehdr *hdr = Base;
62 switch(hdr->e_ident[4])
65 return Elf32Relocate(Base, envp, Filename);
68 return Elf64Relocate(Base, envp, Filename);
71 SysDebug("ld-acess - ElfRelocate: Unknown file class %i", hdr->e_ident[4]);
77 * \fn int ElfGetSymbol(Uint Base, const char *name, void **ret)
79 int ElfGetSymbol(void *Base, const char *Name, void **ret, size_t *Size)
81 Elf32_Ehdr *hdr = Base;
83 switch(hdr->e_ident[4])
86 return Elf32GetSymbol(Base, Name, ret, Size);
89 return Elf64GetSymbol(Base, Name, ret, Size);
92 SysDebug("ld-acess - ElfRelocate: Unknown file class %i", hdr->e_ident[4]);
97 int elf_doRelocate_386(uint32_t r_info, uint32_t *ptr, Elf32_Addr addend, int type,
98 int bRela, const char *Sym, intptr_t iBaseDiff)
103 // Standard 32 Bit Relocation (S+A)
105 if( !GetSymbol(Sym, &symval, NULL) )
107 DEBUGS(" elf_doRelocate: R_386_32 *0x%x += %p('%s')",
109 *ptr = (intptr_t)symval + addend;
112 // 32 Bit Relocation wrt. Offset (S+A-P)
114 DEBUGS(" elf_doRelocate: '%s'", Sym);
115 if( !GetSymbol(Sym, &symval, NULL) ) return 1;
116 DEBUGS(" elf_doRelocate: R_386_PC32 *0x%x = 0x%x + 0x%p - 0x%x",
117 ptr, *ptr, symval, (intptr_t)ptr );
118 *ptr = (intptr_t)symval + addend - (intptr_t)ptr;
119 //*ptr = val + addend - ((Uint)ptr - iBaseDiff);
122 // Absolute Value of a symbol (S)
125 DEBUGS(" elf_doRelocate: '%s'", Sym);
126 if( !GetSymbol(Sym, &symval, NULL) ) return 1;
127 DEBUGS(" elf_doRelocate: %s *0x%x = %p", csaR_NAMES[type], ptr, symval);
128 *ptr = (intptr_t)symval;
131 // Base Address (B+A)
133 DEBUGS(" elf_doRelocate: R_386_RELATIVE *0x%x = 0x%x + 0x%x", ptr, iBaseDiff, addend);
134 *ptr = iBaseDiff + addend;
139 if( !GetSymbol(Sym, &symval, &size) ) return 1;
140 DEBUGS(" elf_doRelocate_386: R_386_COPY (%p, %p, %i)", ptr, symval, size);
141 memcpy(ptr, symval, size);
145 SysDebug("elf_doRelocate_386: Unknown relocation %i", type);
151 int elf_doRelocate_arm(uint32_t r_info, uint32_t *ptr, Elf32_Addr addend, int type, int bRela, const char *Sym, intptr_t iBaseDiff)
158 DEBUGS(" elf_doRelocate_arm: R_ARM_ABS32 %p (%s + %x)", ptr, Sym, addend);
159 if( !GetSymbol(Sym, (void**)&val, NULL) ) return 1;
163 DEBUGS(" elf_doRelocate_arm: R_ARM_GLOB_DAT %p (%s + %x)", ptr, Sym, addend);
164 if( !GetSymbol(Sym, (void**)&val, NULL) ) return 1;
167 case R_ARM_JUMP_SLOT:
168 if(!bRela) addend = 0;
169 DEBUGS(" elf_doRelocate_arm: R_ARM_JUMP_SLOT %p (%s + %x)", ptr, Sym, addend);
170 if( !GetSymbol(Sym, (void**)&val, NULL) ) return 1;
177 if( !GetSymbol(Sym, &src, &size) ) return 1;
178 DEBUGS(" elf_doRelocate_arm: R_ARM_COPY (%p, %p, %i)", ptr, src, size);
179 memcpy(ptr, src, size);
181 // Delta between link and runtime locations + A
183 DEBUGS(" elf_doRelocate_arm: R_ARM_RELATIVE %p (0x%x + 0x%x)", ptr, iBaseDiff, addend);
185 // TODO: Get delta for a symbol
186 SysDebug("elf_doRelocate_arm: TODO - Implment R_ARM_RELATIVE for symbols");
190 *ptr = iBaseDiff + addend;
194 SysDebug("elf_doRelocate_arm: Unknown Relocation, %i", type);
200 int elf_doRelocate_unk(uint32_t r_info, uint32_t *ptr, Elf32_Addr addend, int type, int bRela, const char *Sym, intptr_t iBaseDiff)
205 void *Elf32Relocate(void *Base, char **envp, const char *Filename)
207 Elf32_Ehdr *hdr = Base;
210 intptr_t iRealBase = -1;
213 Elf32_Rel *rel = NULL;
214 Elf32_Rela *rela = NULL;
216 int relSz=0, relEntSz=8;
217 int relaSz=0, relaEntSz=8;
218 int pltSz=0, pltType=0;
219 Elf32_Dyn *dynamicTab = NULL; // Dynamic Table Pointer
220 char *dynstrtab = NULL; // .dynamic String Table
221 Elf32_Sym *dynsymtab;
222 int (*do_relocate)(uint32_t t_info, uint32_t *ptr, Elf32_Addr addend, int Type, int bRela, const char *Sym, intptr_t iBaseDiff);
224 DEBUGS("ElfRelocate: (Base=0x%x)", Base);
226 // Check magic header
229 // Parse Program Header to get Dynamic Table
230 phtab = (void*)( (uintptr_t)Base + hdr->phoff );
231 iSegmentCount = hdr->phentcount;
232 for(int i = 0; i < iSegmentCount; i ++)
234 switch(phtab[i].Type)
237 // Determine linked base address
238 if( iRealBase > phtab[i].VAddr)
239 iRealBase = phtab[i].VAddr;
242 // Find Dynamic Section
244 dynamicTab = (void *) (intptr_t) phtab[i].VAddr;
247 DEBUGS(" WARNING - elf_relocate: Multiple PT_DYNAMIC segments");
253 // Page Align real base
255 DEBUGS(" elf_relocate: True Base = 0x%x, Compiled Base = 0x%x", Base, iRealBase);
257 // Adjust "Real" Base
258 iBaseDiff = (intptr_t)Base - iRealBase;
260 // hdr->entrypoint += iBaseDiff; // Adjust Entrypoint
262 // Check if a PT_DYNAMIC segement was found
264 SysDebug(" elf_relocate: No PT_DYNAMIC segment in image %p, returning", Base);
265 return (void *)(intptr_t)(hdr->entrypoint + iBaseDiff);
268 // Allow writing to read-only segments, just in case they need to be relocated
269 // - Will be reversed at the end of the function
270 for( int i = 0; i < iSegmentCount; i ++ )
272 if(phtab[i].Type == PT_LOAD && !(phtab[i].Flags & PF_W) ) {
273 uintptr_t addr = phtab[i].VAddr + iBaseDiff;
274 uintptr_t end = addr + phtab[i].MemSize;
275 for( ; addr < end; addr += PAGE_SIZE )
276 _SysSetMemFlags(addr, 0, 1); // Unset RO
280 // Adjust Dynamic Table
281 dynamicTab = (void *)( (intptr_t)dynamicTab + iBaseDiff );
283 // === Get Symbol table and String Table ===
285 for( int j = 0; dynamicTab[j].d_tag != DT_NULL; j++)
287 switch(dynamicTab[j].d_tag)
289 // --- Symbol Table ---
291 DEBUGS(" elf_relocate: DYNAMIC Symbol Table 0x%x (0x%x)",
292 dynamicTab[j].d_val, dynamicTab[j].d_val + iBaseDiff);
293 dynsymtab = (void*)((intptr_t)dynamicTab[j].d_val + iBaseDiff);
294 //if(iBaseDiff != 0) dynamicTab[j].d_val += iBaseDiff;
296 // --- String Table ---
298 DEBUGS(" elf_relocate: DYNAMIC String Table 0x%x (0x%x)",
299 dynamicTab[j].d_val, dynamicTab[j].d_val + iBaseDiff);
300 dynstrtab = (void*)((intptr_t)dynamicTab[j].d_val + iBaseDiff);
301 //if(iBaseDiff != 0) dynamicTab[j].d_val += iBaseDiff;
305 //if(iBaseDiff != 0) dynamicTab[j].d_val += iBaseDiff;
306 // iSymCount = ((Elf32_Word*)(intptr_t)dynamicTab[j].d_val)[1];
311 if(dynsymtab == NULL) {
312 SysDebug("ld-acess.so - WARNING: No Dynamic Symbol table in %p, returning", hdr);
313 return (void *)(intptr_t) (hdr->entrypoint + iBaseDiff);
316 // === Add to loaded list (can be imported now) ===
317 AddLoaded( Filename, Base );
319 // === Parse Relocation Data ===
320 DEBUGS(" elf_relocate: dynamicTab = 0x%x", dynamicTab);
321 for( int j = 0; dynamicTab[j].d_tag != DT_NULL; j++)
323 switch(dynamicTab[j].d_tag)
325 // --- Shared Library Name ---
327 DEBUGS(" elf_relocate: .so Name '%s'", dynstrtab+dynamicTab[j].d_val);
329 // --- Needed Library ---
331 libPath = dynstrtab + dynamicTab[j].d_val;
332 DEBUGS(" dynstrtab = %p, d_val = 0x%x", dynstrtab, dynamicTab[j].d_val);
333 DEBUGS(" Required Library '%s'", libPath);
334 if(LoadLibrary(libPath, NULL, envp) == 0) {
336 DEBUGS(" elf_relocate: Unable to load '%s'", libPath);
338 SysDebug("Unable to load required library '%s'", libPath);
342 DEBUGS(" Lib loaded");
345 // case DT_PLTGOT: pltgot = (void*)(iBaseDiff + dynamicTab[j].d_val); break;
346 case DT_JMPREL: plt = (void*)(iBaseDiff + dynamicTab[j].d_val); break;
347 case DT_PLTREL: pltType = dynamicTab[j].d_val; break;
348 case DT_PLTRELSZ: pltSz = dynamicTab[j].d_val; break;
350 // --- Relocation ---
351 case DT_REL: rel = (void*)(iBaseDiff + dynamicTab[j].d_val); break;
352 case DT_RELSZ: relSz = dynamicTab[j].d_val; break;
353 case DT_RELENT: relEntSz = dynamicTab[j].d_val; break;
354 case DT_RELA: rela = (void*)(iBaseDiff + dynamicTab[j].d_val); break;
355 case DT_RELASZ: relaSz = dynamicTab[j].d_val; break;
356 case DT_RELAENT: relaEntSz = dynamicTab[j].d_val; break;
358 // --- Symbol Table ---
360 // --- Hash Table ---
362 // --- String Table ---
368 if(dynamicTab[j].d_tag > DT_JMPREL) continue;
369 //DEBUGS(" elf_relocate: %i-%i = %s,0x%x",
370 // i,j, csaDT_NAMES[dynamicTab[j].d_tag],dynamicTab[j].d_val);
375 DEBUGS(" elf_relocate: Beginning Relocation");
382 do_relocate = elf_doRelocate_386;
385 do_relocate = elf_doRelocate_arm;
388 SysDebug("Elf32Relocate: Unknown machine type %i", hdr->machine);
389 do_relocate = elf_doRelocate_unk;
394 DEBUGS("do_relocate = %p (%p or %p)", do_relocate, &elf_doRelocate_386, &elf_doRelocate_arm);
396 #define _doRelocate(r_info, ptr, bRela, addend) \
397 do_relocate(r_info, ptr, addend, ELF32_R_TYPE(r_info), bRela, \
398 dynstrtab + dynsymtab[ELF32_R_SYM(r_info)].nameOfs, iBaseDiff);
400 // Parse Relocation Entries
404 DEBUGS(" elf_relocate: rel=0x%x, relSz=0x%x, relEntSz=0x%x", rel, relSz, relEntSz);
405 int max = relSz / relEntSz;
406 for( int i = 0; i < max; i++ )
408 //DEBUGS(" Rel %i: 0x%x+0x%x", i, iBaseDiff, rel[i].r_offset);
409 ptr = (void*)(iBaseDiff + rel[i].r_offset);
410 fail |= _doRelocate(rel[i].r_info, ptr, 0, *ptr);
413 // Parse Relocation Entries
417 DEBUGS(" elf_relocate: rela=0x%x, relaSz=0x%x, relaEntSz=0x%x", rela, relaSz, relaEntSz);
418 int count = relaSz / relaEntSz;
419 for( int i = 0; i < count; i++ )
421 ptr = (void*)(iBaseDiff + rela[i].r_offset);
422 fail |= _doRelocate(rel[i].r_info, ptr, 1, rela[i].r_addend);
426 // === Process PLT (Procedure Linkage Table) ===
430 DEBUGS(" elf_relocate: Relocate PLT, plt=0x%x", plt);
431 if(pltType == DT_REL)
433 Elf32_Rel *pltRel = plt;
434 int count = pltSz / sizeof(Elf32_Rel);
435 DEBUGS(" elf_relocate: PLT Reloc Type = Rel, %i entries", count);
436 for(int i = 0; i < count; i ++)
438 ptr = (void*)(iBaseDiff + pltRel[i].r_offset);
439 fail |= _doRelocate(pltRel[i].r_info, ptr, 0, *ptr);
444 Elf32_Rela *pltRela = plt;
445 int count = pltSz / sizeof(Elf32_Rela);
446 DEBUGS(" elf_relocate: PLT Reloc Type = Rela, %i entries", count);
447 for(int i=0;i<count;i++)
449 ptr = (void*)(iRealBase + pltRela[i].r_offset);
450 fail |= _doRelocate(pltRela[i].r_info, ptr, 1, pltRela[i].r_addend);
456 for( int i = 0; i < iSegmentCount; i ++ )
458 // If load and not writable
459 if(phtab[i].Type == PT_LOAD && !(phtab[i].Flags & PF_W) ) {
460 uintptr_t addr = phtab[i].VAddr + iBaseDiff;
461 uintptr_t end = addr + phtab[i].MemSize;
462 for( ; addr < end; addr += PAGE_SIZE )
463 _SysSetMemFlags(addr, 1, 1); // Unset RO
468 DEBUGS("ElfRelocate: Failure");
474 DEBUGS("ElfRelocate: RETURN 0x%x to %p", hdr->entrypoint + iBaseDiff, __builtin_return_address(0));
475 return (void*)(intptr_t)( hdr->entrypoint + iBaseDiff );
478 int Elf32GetSymbol(void *Base, const char *Name, void **ret, size_t *Size)
480 Elf32_Ehdr *hdr = Base;
481 Elf32_Sym *symtab = NULL;
483 Elf32_Word *pBuckets = NULL;
486 const char *dynstrtab = NULL;
487 uintptr_t iBaseDiff = -1;
489 Elf32_Dyn *dynTab = NULL;
492 phtab = (void*)( (uintptr_t)Base + hdr->phoff );
493 for( int i = 0; i < hdr->phentcount; i ++ )
495 if(phtab[i].Type == PT_LOAD && iBaseDiff > phtab[i].VAddr)
496 iBaseDiff = phtab[i].VAddr;
497 if( phtab[i].Type == PT_DYNAMIC ) {
498 dynTab = (void*)(intptr_t)phtab[i].VAddr;
502 SysDebug("ERROR - Unable to find DYNAMIC segment in %p", Base);
505 iBaseDiff = (intptr_t)Base - iBaseDiff; // Make iBaseDiff actually the diff
506 dynTab = (void*)( (intptr_t)dynTab + iBaseDiff );
507 for( int i = 0; dynTab[i].d_tag != DT_NULL; i++)
509 switch(dynTab[i].d_tag)
511 // --- Symbol Table ---
513 symtab = (void*)((intptr_t)dynTab[i].d_val + iBaseDiff); // Rebased in Relocate
516 dynstrtab = (void*)((intptr_t)dynTab[i].d_val + iBaseDiff);
520 pBuckets = (void*)((intptr_t)dynTab[i].d_val + iBaseDiff);
526 SysDebug("ERRO - No DT_SYMTAB in %p", Base);
530 SysDebug("ERRO - No DT_HASH in %p", Base);
534 SysDebug("ERRO - No DT_STRTAB in %p", Base);
538 // ... ok... maybe they haven't been relocated
539 if( (uintptr_t)symtab < (uintptr_t)Base )
541 symtab = (void*)( (uintptr_t)symtab + iBaseDiff );
542 pBuckets = (void*)( (uintptr_t)pBuckets + iBaseDiff );
543 dynstrtab = (void*)( (uintptr_t)dynstrtab + iBaseDiff );
544 SysDebug("Executable not yet relocated");
547 nbuckets = pBuckets[0];
548 // iSymCount = pBuckets[1];
549 pBuckets = &pBuckets[2];
550 pChains = &pBuckets[ nbuckets ];
554 iNameHash = ElfHashString(Name);
555 iNameHash %= nbuckets;
558 int idx = pBuckets[ iNameHash ];
560 Elf32_Sym *sym = &symtab[idx];
562 if(sym->shndx != SHN_UNDEF && strcmp(dynstrtab + sym->nameOfs, Name) == 0) {
563 *ret = (void*)( (uintptr_t)sym->value + iBaseDiff );
564 if(Size) *Size = sym->size;
567 } while( (idx = pChains[idx]) != STN_UNDEF && idx != pBuckets[iNameHash] );
573 typedef int (*t_elf64_doreloc)(void *Base, const char *strtab, Elf64_Sym *symtab, Elf64_Xword r_info, void *ptr, Elf64_Sxword addend);
575 int _Elf64DoReloc_X86_64(void *Base, const char *strtab, Elf64_Sym *symtab, Elf64_Xword r_info, void *ptr, Elf64_Sxword addend)
577 int sym = ELF64_R_SYM(r_info);
578 int type = ELF64_R_TYPE(r_info);
579 const char *symname = strtab + symtab[sym].st_name;
581 //DEBUGS("_Elf64DoReloc: %s", symname);
587 if( !GetSymbol(symname, &symval, NULL) ) return 1;
588 *(uint64_t*)ptr = (uintptr_t)symval + addend;
590 case R_X86_64_COPY: {
592 if( !GetSymbol(symname, &symval, &size) ) return 1;
593 memcpy(ptr, symval, size);
595 case R_X86_64_GLOB_DAT:
596 if( !GetSymbol(symname, &symval, NULL) ) return 1;
597 *(uint64_t*)ptr = (uintptr_t)symval;
599 case R_X86_64_JUMP_SLOT:
600 if( !GetSymbol(symname, &symval, NULL) ) return 1;
601 *(uint64_t*)ptr = (uintptr_t)symval;
603 case R_X86_64_RELATIVE:
604 *(uint64_t*)ptr = (uintptr_t)Base + addend;
607 SysDebug("ld-acess - _Elf64DoReloc: Unknown relocation type %i", type);
610 //DEBUGS("_Elf64DoReloc: - Good");
614 void *Elf64Relocate(void *Base, char **envp, const char *Filename)
617 Elf64_Ehdr *hdr = Base;
619 Elf64_Dyn *dyntab = NULL;
620 Elf64_Addr compiledBase = -1, baseDiff;
621 Elf64_Sym *symtab = NULL;
623 Elf64_Word *hashtab = NULL;
624 Elf64_Rel *rel = NULL;
626 Elf64_Rela *rela = NULL;
629 int plt_size = 0, plt_type = 0;
631 DEBUGS("Elf64Relocate: hdr = {");
632 DEBUGS("Elf64Relocate: e_ident = '%.16s'", hdr->e_ident);
633 DEBUGS("Elf64Relocate: e_type = 0x%x", hdr->e_type);
634 DEBUGS("Elf64Relocate: e_machine = 0x%x", hdr->e_machine);
635 DEBUGS("Elf64Relocate: e_version = 0x%x", hdr->e_version);
636 DEBUGS("Elf64Relocate: e_entry = %p", hdr->e_entry);
637 DEBUGS("Elf64Relocate: e_phoff = 0x%llx", hdr->e_phoff);
638 DEBUGS("Elf64Relocate: e_shoff = 0x%llx", hdr->e_shoff);
639 DEBUGS("Elf64Relocate: e_flags = 0x%x", hdr->e_flags);
640 DEBUGS("Elf64Relocate: e_ehsize = 0x%x", hdr->e_ehsize);
641 DEBUGS("Elf64Relocate: e_phentsize = 0x%x", hdr->e_phentsize);
642 DEBUGS("Elf64Relocate: e_phnum = %i", hdr->e_phnum);
644 // Scan for the dynamic table (and find the compiled base)
645 phtab = (void*)((uintptr_t)Base + (uintptr_t)hdr->e_phoff);
646 for( i = 0; i < hdr->e_phnum; i ++ )
648 if(phtab[i].p_type == PT_DYNAMIC)
649 dyntab = (void *)(intptr_t)phtab[i].p_vaddr;
650 if(phtab[i].p_type == PT_LOAD && compiledBase > phtab[i].p_vaddr)
651 compiledBase = phtab[i].p_vaddr;
654 baseDiff = (uintptr_t)Base - compiledBase;
656 DEBUGS("baseDiff = %p", baseDiff);
659 SysDebug(" Elf64Relocate: No PT_DYNAMIC segment in image %p, returning", Base);
660 return (void *)(uintptr_t)(hdr->e_entry + baseDiff);
663 dyntab = (void *)(uintptr_t)((uintptr_t)dyntab + baseDiff);
665 // Parse the dynamic table (first pass)
666 // - Search for String, Symbol and Hash tables
667 for(i = 0; dyntab[i].d_tag != DT_NULL; i ++)
669 switch(dyntab[i].d_tag)
672 dyntab[i].d_un.d_ptr += baseDiff;
673 symtab = (void *)(uintptr_t)dyntab[i].d_un.d_ptr;
676 dyntab[i].d_un.d_ptr += baseDiff;
677 strtab = (void *)(uintptr_t)dyntab[i].d_un.d_ptr;
680 dyntab[i].d_un.d_ptr += baseDiff;
681 hashtab = (void *)(uintptr_t)dyntab[i].d_un.d_ptr;
686 if( !symtab || !strtab || !hashtab ) {
687 SysDebug("ld-acess - Elf64Relocate: Missing Symbol, string or hash table");
691 // Ready for symbol use
692 AddLoaded( Filename, Base );
694 // Second pass on dynamic table
695 for(i = 0; dyntab[i].d_tag != DT_NULL; i ++)
697 DEBUGS("dyntab[%i].d_tag = %i", i, dyntab[i].d_tag);
698 switch(dyntab[i].d_tag)
700 case DT_SONAME: break;
703 char *libPath = strtab + dyntab[i].d_un.d_val;
704 DEBUGS("Elf64Relocate: libPath = '%s'", libPath);
705 if(LoadLibrary(libPath, NULL, envp) == 0) {
706 SysDebug("ld-acess - Elf64Relocate: Unable to load '%s'", libPath);
711 // Relocation entries
713 dyntab[i].d_un.d_ptr += baseDiff;
714 rel = (void *)(uintptr_t)dyntab[i].d_un.d_ptr;
717 rel_count = dyntab[i].d_un.d_val / sizeof(Elf64_Rel);
720 if( dyntab[i].d_un.d_val != sizeof(Elf64_Rel) ) {
721 SysDebug("ld-acess - Elf64Relocate: DT_RELENT(%i) != sizeof(Elf64_Rel)(%i)",
722 dyntab[i].d_un.d_val, sizeof(Elf64_Rel));
727 dyntab[i].d_un.d_ptr += baseDiff;
728 rela = (void *)(uintptr_t)dyntab[i].d_un.d_ptr;
731 rela_count = dyntab[i].d_un.d_val / sizeof(Elf64_Rela);
734 if( dyntab[i].d_un.d_val != sizeof(Elf64_Rela) ) {
735 SysDebug("ld-acess - Elf64Relocate: DT_RELAENT(%i) != sizeof(Elf64_Rela)(%i)",
736 dyntab[i].d_un.d_val, sizeof(Elf64_Rela));
741 dyntab[i].d_un.d_ptr += baseDiff;
742 pltrel = (void *)(uintptr_t)dyntab[i].d_un.d_ptr;
745 plt_type = dyntab[i].d_un.d_val;
748 plt_size = dyntab[i].d_un.d_val;
753 // Relocation function
754 t_elf64_doreloc fpElf64DoReloc = &_Elf64DoReloc_X86_64;
755 #define _Elf64DoReloc(info, ptr, addend) fpElf64DoReloc(Base, strtab, symtab, info, ptr, addend)
760 DEBUGS("rel_count = %i", rel_count);
761 for( i = 0; i < rel_count; i ++ )
763 uint64_t *ptr = (void *)(uintptr_t)( rel[i].r_offset + baseDiff );
764 fail |= _Elf64DoReloc( rel[i].r_info, ptr, *ptr);
770 DEBUGS("rela_count = %i", rela_count);
771 for( i = 0; i < rela_count; i ++ )
773 uint64_t *ptr = (void *)(uintptr_t)( rela[i].r_offset + baseDiff );
774 fail |= _Elf64DoReloc( rela[i].r_info, ptr, rela[i].r_addend );
778 if( pltrel && plt_type )
780 if( plt_type == DT_REL ) {
781 Elf64_Rel *plt = pltrel;
782 int count = plt_size / sizeof(Elf64_Rel);
783 DEBUGS("plt rel count = %i", count);
784 for( i = 0; i < count; i ++ )
786 uint64_t *ptr = (void *)(uintptr_t)( plt[i].r_offset + baseDiff );
787 fail |= _Elf64DoReloc( plt[i].r_info, ptr, *ptr);
791 Elf64_Rela *plt = pltrel;
792 int count = plt_size / sizeof(Elf64_Rela);
793 DEBUGS("plt rela count = %i", count);
794 for( i = 0; i < count; i ++ )
796 uint64_t *ptr = (void *)(uintptr_t)( plt[i].r_offset + baseDiff );
797 fail |= _Elf64DoReloc( plt[i].r_info, ptr, plt[i].r_addend);
803 DEBUGS("Elf64Relocate: Failure");
808 void *ret = (void *)(uintptr_t)(hdr->e_entry + baseDiff);
809 DEBUGS("Elf64Relocate: Relocations done, return %p", ret);
814 int Elf64GetSymbol(void *Base, const char *Name, void **Ret, size_t *Size)
816 Elf64_Ehdr *hdr = Base;
819 // int iSymCount = 0;
821 Elf64_Word *pBuckets;
824 const char *dynstrtab;
825 uintptr_t iBaseDiff = -1;
831 // Catch the current executable
835 Elf64_Dyn *dynTab = NULL;
839 phtab = (void*)( (intptr_t)Base + (uintptr_t)hdr->e_phoff );
840 for( i = 0; i < hdr->e_phnum; i ++ )
842 if(phtab[i].p_type == PT_LOAD && iBaseDiff > phtab[i].p_vaddr)
843 iBaseDiff = phtab[i].p_vaddr;
844 if( phtab[i].p_type == PT_DYNAMIC ) {
845 dynTab = (void*)(intptr_t)phtab[i].p_vaddr;
849 SysDebug("ERROR - Unable to find DYNAMIC segment in %p", Base);
852 iBaseDiff = (intptr_t)Base - iBaseDiff; // Make iBaseDiff actually the diff
853 dynTab = (void*)( (intptr_t)dynTab + iBaseDiff );
855 for( j = 0; dynTab[j].d_tag != DT_NULL; j++)
857 switch(dynTab[j].d_tag)
859 // --- Symbol Table ---
861 symtab = (void*)(intptr_t) dynTab[j].d_un.d_val; // Rebased in Relocate
864 dynstrtab = (void*)(intptr_t) dynTab[j].d_un.d_val;
868 pBuckets = (void*)(intptr_t) dynTab[j].d_un.d_val;
874 nbuckets = pBuckets[0];
875 // iSymCount = pBuckets[1];
876 pBuckets = &pBuckets[2];
877 pChains = &pBuckets[ nbuckets ];
880 iNameHash = ElfHashString(Name);
881 iNameHash %= nbuckets;
884 i = pBuckets[ iNameHash ];
885 if(symtab[i].st_shndx != SHN_UNDEF && strcmp(dynstrtab + symtab[i].st_name, Name) == 0) {
886 *Ret = (void*)( (intptr_t)symtab[i].st_value + iBaseDiff );
887 if(Size) *Size = symtab[i].st_size;
888 DEBUGS("%s = %p", Name, *Ret);
892 while(pChains[i] != STN_UNDEF)
895 if(symtab[i].st_shndx != SHN_UNDEF && strcmp(dynstrtab + symtab[i].st_name, Name) == 0) {
896 *Ret = (void*)((intptr_t)symtab[i].st_value + iBaseDiff);
897 if(Size) *Size = symtab[i].st_size;
898 DEBUGS("%s = %p", Name, *Ret);
908 uint32_t ElfHashString(const char *name)
913 h = (h << 4) + *(uint8_t*)name++;
914 if( (g = h & 0xf0000000) )