X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Usermode%2FLibraries%2Fld-acess.so_src%2Felf.c;h=995d5ea7386a22500244c5483a594d9f88e35e07;hb=92e1384ea0be30ae9ab82af6864da2806286e864;hp=bcec1dc664dbd3d027e286409dcd72b3746a3b9b;hpb=3d6a345b39afa454f0f33fc8d48b96229971e6ed;p=tpg%2Facess2.git diff --git a/Usermode/Libraries/ld-acess.so_src/elf.c b/Usermode/Libraries/ld-acess.so_src/elf.c index bcec1dc6..995d5ea7 100644 --- a/Usermode/Libraries/ld-acess.so_src/elf.c +++ b/Usermode/Libraries/ld-acess.so_src/elf.c @@ -1,19 +1,27 @@ /* - * AcessOS 1 - Dynamic Loader - * By thePowersGang + * Acess2 Dynamic Linker + * - By John Hodge (thePowersGang) + * + * elf.c + * - ELF32/ELF64 relocation */ +#define DEBUG 0 + #include "common.h" #include #include "elf32.h" - -#define DEBUG 0 +#include "elf64.h" #if DEBUG -# define DEBUGS(v...) SysDebug(v) +# define DEBUGS(v...) SysDebug("ld-acess - " v) #else # define DEBUGS(...) #endif +//#if BITS > 32 +# define SUPPORT_ELF64 +//#endif + // === CONSTANTS === #if DEBUG //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"}; @@ -21,27 +29,168 @@ static const char *csaR_NAMES[] = {"R_386_NONE", "R_386_32", "R_386_PC32", "R_38 #endif // === PROTOTYPES === -void elf_doRelocate(Uint r_info, Uint32 *ptr, Uint32 addend, Elf32_Sym *symtab, Uint base); -Uint ElfHashString(char *name); +void *ElfRelocate(void *Base, char **envp, const char *Filename); + int ElfGetSymbol(void *Base, const char *Name, void **Ret, size_t *Size); +void *Elf32Relocate(void *Base, char **envp, const char *Filename); + int Elf32GetSymbol(void *Base, const char *Name, void **Ret, size_t *Size); +#ifdef SUPPORT_ELF64 +void *Elf64Relocate(void *Base, char **envp, const char *Filename); + int Elf64GetSymbol(void *Base, const char *Name, void **Ret, size_t *Size); +#endif +uint32_t ElfHashString(const char *name); // === CODE === /** - \fn int ElfRelocate(void *Base, char **envp, char *Filename) - \brief Relocates a loaded ELF Executable -*/ -void *ElfRelocate(void *Base, char **envp, char *Filename) + * \fn int ElfRelocate(void *Base, char **envp, const char *Filename) + * \brief Relocates a loaded ELF Executable + */ +void *ElfRelocate(void *Base, char **envp, const char *Filename) +{ + Elf32_Ehdr *hdr = Base; + + switch(hdr->e_ident[4]) + { + case ELFCLASS32: + return Elf32Relocate(Base, envp, Filename); +#ifdef SUPPORT_ELF64 + case ELFCLASS64: + return Elf64Relocate(Base, envp, Filename); +#endif + default: + SysDebug("ld-acess - ElfRelocate: Unknown file class %i", hdr->e_ident[4]); + return NULL; + } +} + +/** + * \fn int ElfGetSymbol(Uint Base, const char *name, void **ret) + */ +int ElfGetSymbol(void *Base, const char *Name, void **ret, size_t *Size) +{ + Elf32_Ehdr *hdr = Base; + + switch(hdr->e_ident[4]) + { + case ELFCLASS32: + return Elf32GetSymbol(Base, Name, ret, Size); +#ifdef SUPPORT_ELF64 + case ELFCLASS64: + return Elf64GetSymbol(Base, Name, ret, Size); +#endif + default: + SysDebug("ld-acess - ElfRelocate: Unknown file class %i", hdr->e_ident[4]); + return 0; + } +} + +void elf_doRelocate_386(uint32_t r_info, uint32_t *ptr, Elf32_Addr addend, int type, int bRela, const char *Sym, intptr_t iBaseDiff) +{ + intptr_t val; + switch( type ) + { + // Standard 32 Bit Relocation (S+A) + case R_386_32: + val = (intptr_t) GetSymbol(Sym, NULL); + DEBUGS(" elf_doRelocate: R_386_32 *0x%x += 0x%x('%s')", + ptr, val, Sym); + *ptr = val + addend; + break; + + // 32 Bit Relocation wrt. Offset (S+A-P) + case R_386_PC32: + DEBUGS(" elf_doRelocate: '%s'", Sym); + val = (intptr_t) GetSymbol(Sym, NULL); + DEBUGS(" elf_doRelocate: R_386_PC32 *0x%x = 0x%x + 0x%x - 0x%x", + ptr, *ptr, val, (intptr_t)ptr ); + *ptr = val + addend - (intptr_t)ptr; + //*ptr = val + addend - ((Uint)ptr - iBaseDiff); + break; + + // Absolute Value of a symbol (S) + case R_386_GLOB_DAT: + case R_386_JMP_SLOT: + DEBUGS(" elf_doRelocate: '%s'", Sym); + val = (intptr_t) GetSymbol( Sym, NULL ); + DEBUGS(" elf_doRelocate: %s *0x%x = 0x%x", csaR_NAMES[type], ptr, val); + *ptr = val; + break; + + // Base Address (B+A) + case R_386_RELATIVE: + DEBUGS(" elf_doRelocate: R_386_RELATIVE *0x%x = 0x%x + 0x%x", ptr, iBaseDiff, addend); + *ptr = iBaseDiff + addend; + break; + + case R_386_COPY: { + size_t size; + void *src = GetSymbol(Sym, &size); + DEBUGS(" elf_doRelocate_386: R_386_COPY (%p, %p, %i)", ptr, src, size); + memcpy(ptr, src, size); + break; } + + default: + SysDebug("elf_doRelocate_386: Unknown relocation %i", type); + break; + } +} + +void elf_doRelocate_arm(uint32_t r_info, uint32_t *ptr, Elf32_Addr addend, int type, int bRela, const char *Sym, intptr_t iBaseDiff) +{ + uint32_t val; + switch(type) + { + // (S + A) | T + case R_ARM_ABS32: + DEBUGS(" elf_doRelocate_arm: R_ARM_ABS32 %p (%s + %x)", ptr, Sym, addend); + val = (intptr_t)GetSymbol(Sym, NULL); + *ptr = val + addend; + break; + case R_ARM_GLOB_DAT: + DEBUGS(" elf_doRelocate_arm: R_ARM_GLOB_DAT %p (%s + %x)", ptr, Sym, addend); + val = (intptr_t)GetSymbol(Sym, NULL); + *ptr = val + addend; + break; + case R_ARM_JUMP_SLOT: + if(!bRela) addend = 0; + DEBUGS(" elf_doRelocate_arm: R_ARM_JUMP_SLOT %p (%s + %x)", ptr, Sym, addend); + val = (intptr_t)GetSymbol(Sym, NULL); + *ptr = val + addend; + break; + // Copy + case R_ARM_COPY: { + size_t size; + void *src = GetSymbol(Sym, &size); + DEBUGS(" elf_doRelocate_arm: R_ARM_COPY (%p, %p, %i)", ptr, src, size); + memcpy(ptr, src, size); + break; } + // Delta between link and runtime locations + A + case R_ARM_RELATIVE: + if(Sym[0] != '\0') { + // TODO: Get delta for a symbol + SysDebug("elf_doRelocate_arm: TODO - Implment R_ARM_RELATIVE for symbols"); + } + else { + *ptr = iBaseDiff + addend; + } + break; + default: + SysDebug("elf_doRelocate_arm: Unknown Relocation, %i", type); + break; + } +} + +void *Elf32Relocate(void *Base, char **envp, const char *Filename) { Elf32_Ehdr *hdr = Base; Elf32_Phdr *phtab; int i, j; // Counters char *libPath; - Uint iRealBase = -1; - Uint iBaseDiff; + intptr_t iRealBase = -1; + intptr_t iBaseDiff; int iSegmentCount; - int iSymCount; +// int iSymCount; Elf32_Rel *rel = NULL; Elf32_Rela *rela = NULL; - Uint32 *pltgot = NULL; void *plt = NULL; int relSz=0, relEntSz=8; int relaSz=0, relaEntSz=8; @@ -49,8 +198,9 @@ void *ElfRelocate(void *Base, char **envp, char *Filename) Elf32_Dyn *dynamicTab = NULL; // Dynamic Table Pointer char *dynstrtab = NULL; // .dynamic String Table Elf32_Sym *dynsymtab; + void (*do_relocate)(uint32_t t_info, uint32_t *ptr, Elf32_Addr addend, int Type, int bRela, const char *Sym, intptr_t iBaseDiff); - DEBUGS("ElfRelocate: (Base=0x%x)\n", Base); + DEBUGS("ElfRelocate: (Base=0x%x)", Base); // Check magic header @@ -67,7 +217,7 @@ void *ElfRelocate(void *Base, char **envp, char *Filename) // Find Dynamic Section if(phtab[i].Type == PT_DYNAMIC) { if(dynamicTab) { - DEBUGS(" WARNING - elf_relocate: Multiple PT_DYNAMIC segments\n"); + DEBUGS(" WARNING - elf_relocate: Multiple PT_DYNAMIC segments"); continue; } dynamicTab = (void *) (intptr_t) phtab[i].VAddr; @@ -77,17 +227,17 @@ void *ElfRelocate(void *Base, char **envp, char *Filename) // Page Align real base iRealBase &= ~0xFFF; - DEBUGS(" elf_relocate: True Base = 0x%x, Compiled Base = 0x%x\n", Base, iRealBase); + DEBUGS(" elf_relocate: True Base = 0x%x, Compiled Base = 0x%x", Base, iRealBase); // Adjust "Real" Base iBaseDiff = (intptr_t)Base - iRealBase; - hdr->entrypoint += iBaseDiff; // Adjust Entrypoint +// hdr->entrypoint += iBaseDiff; // Adjust Entrypoint // Check if a PT_DYNAMIC segement was found if(!dynamicTab) { - SysDebug(" elf_relocate: No PT_DYNAMIC segment in image, returning\n"); - return (void *)hdr->entrypoint; + SysDebug(" elf_relocate: No PT_DYNAMIC segment in image %p, returning", Base); + return (void *)(intptr_t)(hdr->entrypoint + iBaseDiff); } // Adjust Dynamic Table @@ -100,69 +250,60 @@ void *ElfRelocate(void *Base, char **envp, char *Filename) { // --- Symbol Table --- case DT_SYMTAB: - DEBUGS(" elf_relocate: DYNAMIC Symbol Table 0x%x (0x%x)\n", + DEBUGS(" elf_relocate: DYNAMIC Symbol Table 0x%x (0x%x)", dynamicTab[j].d_val, dynamicTab[j].d_val + iBaseDiff); - dynamicTab[j].d_val += iBaseDiff; - dynsymtab = (void*)(dynamicTab[j].d_val); - hdr->misc.SymTable = dynamicTab[j].d_val; // Saved in unused bytes of ident + if(iBaseDiff != 0) dynamicTab[j].d_val += iBaseDiff; + dynsymtab = (void*)(intptr_t)dynamicTab[j].d_val; break; // --- String Table --- case DT_STRTAB: - DEBUGS(" elf_relocate: DYNAMIC String Table 0x%x (0x%x)\n", + DEBUGS(" elf_relocate: DYNAMIC String Table 0x%x (0x%x)", dynamicTab[j].d_val, dynamicTab[j].d_val + iBaseDiff); - dynamicTab[j].d_val += iBaseDiff; - dynstrtab = (void*)(dynamicTab[j].d_val); + if(iBaseDiff != 0) dynamicTab[j].d_val += iBaseDiff; + dynstrtab = (void*)(intptr_t)dynamicTab[j].d_val; break; // --- Hash Table -- case DT_HASH: - dynamicTab[j].d_val += iBaseDiff; - iSymCount = ((Uint*)(dynamicTab[j].d_val))[1]; - hdr->misc.HashTable = dynamicTab[j].d_val; // Saved in unused bytes of ident + if(iBaseDiff != 0) dynamicTab[j].d_val += iBaseDiff; +// iSymCount = ((Elf32_Word*)(intptr_t)dynamicTab[j].d_val)[1]; break; } } if(dynsymtab == NULL) { - SysDebug("ld-acess.so - WARNING: No Dynamic Symbol table, returning\n"); - return (void *) hdr->entrypoint; - } - - // Alter Symbols to true base - for(i=0;ientrypoint + iBaseDiff); } - + // === Add to loaded list (can be imported now) === AddLoaded( Filename, Base ); // === Parse Relocation Data === - DEBUGS(" elf_relocate: dynamicTab = 0x%x\n", dynamicTab); + DEBUGS(" elf_relocate: dynamicTab = 0x%x", dynamicTab); for( j = 0; dynamicTab[j].d_tag != DT_NULL; j++) { switch(dynamicTab[j].d_tag) { // --- Shared Library Name --- case DT_SONAME: - DEBUGS(" elf_relocate: .so Name '%s'\n", dynstrtab+dynamicTab[j].d_val); + DEBUGS(" elf_relocate: .so Name '%s'", dynstrtab+dynamicTab[j].d_val); break; // --- Needed Library --- case DT_NEEDED: libPath = dynstrtab + dynamicTab[j].d_val; - DEBUGS(" Required Library '%s'\n", libPath); + DEBUGS(" Required Library '%s'", libPath); if(LoadLibrary(libPath, NULL, envp) == 0) { #if DEBUG - DEBUGS(" elf_relocate: Unable to load '%s'\n", libPath); + DEBUGS(" elf_relocate: Unable to load '%s'", libPath); #else - SysDebug("Unable to load required library '%s'\n", libPath); + SysDebug("Unable to load required library '%s'", libPath); #endif return 0; } + DEBUGS(" Lib loaded"); break; // --- PLT/GOT --- - case DT_PLTGOT: pltgot = (void*)(iBaseDiff + dynamicTab[j].d_val); break; +// case DT_PLTGOT: pltgot = (void*)(iBaseDiff + dynamicTab[j].d_val); break; case DT_JMPREL: plt = (void*)(iBaseDiff + dynamicTab[j].d_val); break; case DT_PLTREL: pltType = dynamicTab[j].d_val; break; case DT_PLTRELSZ: pltSz = dynamicTab[j].d_val; break; @@ -186,157 +327,439 @@ void *ElfRelocate(void *Base, char **envp, char *Filename) // --- Unknown --- default: if(dynamicTab[j].d_tag > DT_JMPREL) continue; - //DEBUGS(" elf_relocate: %i-%i = %s,0x%x\n", + //DEBUGS(" elf_relocate: %i-%i = %s,0x%x", // i,j, csaDT_NAMES[dynamicTab[j].d_tag],dynamicTab[j].d_val); break; } } - DEBUGS(" elf_relocate: Beginning Relocation\n"); + DEBUGS(" elf_relocate: Beginning Relocation"); + + void _doRelocate(uint32_t r_info, uint32_t *ptr, int bRela, Elf32_Addr addend) + { + int type = ELF32_R_TYPE(r_info); + int sym = ELF32_R_SYM(r_info); + const char *symname = dynstrtab + dynsymtab[sym].nameOfs; + do_relocate(r_info, ptr, addend, type, bRela, symname, iBaseDiff); + } + + switch(hdr->machine) + { + case EM_386: + do_relocate = elf_doRelocate_386; + break; + case EM_ARM: + do_relocate = elf_doRelocate_arm; + break; + default: + SysDebug("Elf32Relocate: Unknown machine type %i", hdr->machine); + break; + } + DEBUGS("do_relocate = %p (%p or %p)", do_relocate, &elf_doRelocate_386, &elf_doRelocate_arm); + // Parse Relocation Entries if(rel && relSz) { - Uint32 *ptr; - DEBUGS(" elf_relocate: rel=0x%x, relSz=0x%x, relEntSz=0x%x\n", rel, relSz, relEntSz); + Elf32_Word *ptr; + DEBUGS(" elf_relocate: rel=0x%x, relSz=0x%x, relEntSz=0x%x", rel, relSz, relEntSz); j = relSz / relEntSz; for( i = 0; i < j; i++ ) { - //DEBUGS(" Rel %i: 0x%x+0x%x\n", i, iBaseDiff, rel[i].r_offset); + //DEBUGS(" Rel %i: 0x%x+0x%x", i, iBaseDiff, rel[i].r_offset); ptr = (void*)(iBaseDiff + rel[i].r_offset); - elf_doRelocate(rel[i].r_info, ptr, *ptr, dynsymtab, iBaseDiff); + _doRelocate(rel[i].r_info, ptr, 0, *ptr); } } // Parse Relocation Entries if(rela && relaSz) { - Uint32 *ptr; - DEBUGS(" elf_relocate: rela=0x%x, relaSz=0x%x, relaEntSz=0x%x\n", rela, relaSz, relaEntSz); + Elf32_Word *ptr; + DEBUGS(" elf_relocate: rela=0x%x, relaSz=0x%x, relaEntSz=0x%x", rela, relaSz, relaEntSz); j = relaSz / relaEntSz; for( i = 0; i < j; i++ ) { ptr = (void*)(iBaseDiff + rela[i].r_offset); - elf_doRelocate(rel[i].r_info, ptr, rela[i].r_addend, dynsymtab, iBaseDiff); + _doRelocate(rel[i].r_info, ptr, 1, rela[i].r_addend); } } // === Process PLT (Procedure Linkage Table) === if(plt && pltSz) { - Uint32 *ptr; - DEBUGS(" elf_relocate: Relocate PLT, plt=0x%x\n", plt); + Elf32_Word *ptr; + DEBUGS(" elf_relocate: Relocate PLT, plt=0x%x", plt); if(pltType == DT_REL) { Elf32_Rel *pltRel = plt; j = pltSz / sizeof(Elf32_Rel); - DEBUGS(" elf_relocate: PLT Reloc Type = Rel, %i entries\n", j); + DEBUGS(" elf_relocate: PLT Reloc Type = Rel, %i entries", j); for(i=0;ientrypoint); - return (void*)hdr->entrypoint; + DEBUGS("ElfRelocate: RETURN 0x%x to %p", hdr->entrypoint + iBaseDiff, __builtin_return_address(0)); + return (void*)(intptr_t)( hdr->entrypoint + iBaseDiff ); } -void elf_doRelocate(Uint r_info, Uint32 *ptr, Uint32 addend, Elf32_Sym *symtab, Uint base) +int Elf32GetSymbol(void *Base, const char *Name, void **ret, size_t *Size) { - int type = ELF32_R_TYPE(r_info); - int sym = ELF32_R_SYM(r_info); - Uint32 val; - switch( type ) + Elf32_Ehdr *hdr = Base; + Elf32_Sym *symtab; + int nbuckets = 0; +// int iSymCount = 0; + int i; + Elf32_Word *pBuckets; + Elf32_Word *pChains; + uint32_t iNameHash; + const char *dynstrtab; + uintptr_t iBaseDiff = -1; + Elf32_Phdr *phtab; + Elf32_Dyn *dynTab = NULL; + + // Locate the tables + phtab = (void*)( Base + hdr->phoff ); + for( i = 0; i < hdr->phentcount; i ++ ) { - // Standard 32 Bit Relocation (S+A) - case R_386_32: - val = (intptr_t) GetSymbol( symtab[sym].name ); - DEBUGS(" elf_doRelocate: R_386_32 *0x%x += 0x%x('%s')\n", - ptr, val, symtab[sym].name); - *ptr = val + addend; - break; - - // 32 Bit Relocation wrt. Offset (S+A-P) - case R_386_PC32: - DEBUGS(" elf_doRelocate: #%i: '%s'\n", sym, symtab[sym].name); - val = (intptr_t) GetSymbol( symtab[sym].name ); - DEBUGS(" elf_doRelocate: R_386_PC32 *0x%x = 0x%x + 0x%x - 0x%x\n", - ptr, *ptr, val, (Uint)ptr ); - *ptr = val + addend - (intptr_t)ptr; - //*ptr = val + addend - ((Uint)ptr - base); - break; + if(phtab[i].Type == PT_LOAD && iBaseDiff > phtab[i].VAddr) + iBaseDiff = phtab[i].VAddr; + if( phtab[i].Type == PT_DYNAMIC ) { + dynTab = (void*)(intptr_t)phtab[i].VAddr; + } + } + if( !dynTab ) { + SysDebug("ERROR - Unable to find DYNAMIC segment in %p", Base); + return 0; + } + iBaseDiff = (intptr_t)Base - iBaseDiff; // Make iBaseDiff actually the diff + dynTab = (void*)( (intptr_t)dynTab + iBaseDiff ); + for( i = 0; dynTab[i].d_tag != DT_NULL; i++) + { + switch(dynTab[i].d_tag) + { + // --- Symbol Table --- + case DT_SYMTAB: + symtab = (void*)(intptr_t) dynTab[i].d_val; // Rebased in Relocate + break; + case DT_STRTAB: + dynstrtab = (void*)(intptr_t) dynTab[i].d_val; + break; + // --- Hash Table -- + case DT_HASH: + pBuckets = (void*)(intptr_t) dynTab[i].d_val; + break; + } + } + + nbuckets = pBuckets[0]; +// iSymCount = pBuckets[1]; + pBuckets = &pBuckets[2]; + pChains = &pBuckets[ nbuckets ]; + + // Get hash + iNameHash = ElfHashString(Name); + iNameHash %= nbuckets; - // Absolute Value of a symbol (S) - case R_386_GLOB_DAT: - case R_386_JMP_SLOT: - DEBUGS(" elf_doRelocate: #%i: '%s'\n", sym, symtab[sym].name); - val = (intptr_t) GetSymbol( symtab[sym].name ); - DEBUGS(" elf_doRelocate: %s *0x%x = 0x%x\n", csaR_NAMES[type], ptr, val); - *ptr = val; - break; + // Walk Chain + i = pBuckets[ iNameHash ]; + if(symtab[i].shndx != SHN_UNDEF && strcmp(dynstrtab + symtab[i].nameOfs, Name) == 0) { + *ret = (void*) (intptr_t) symtab[ i ].value + iBaseDiff; + if(Size) *Size = symtab[i].size; + return 1; + } + + while(pChains[i] != STN_UNDEF) + { + i = pChains[i]; + if(symtab[i].shndx != SHN_UNDEF && strcmp(dynstrtab + symtab[ i ].nameOfs, Name) == 0) { + *ret = (void*)(intptr_t)symtab[ i ].value + iBaseDiff; + if(Size) *Size = symtab[i].size; + return 1; + } + } + + return 0; +} - // Base Address (B+A) - case R_386_RELATIVE: - DEBUGS(" elf_doRelocate: R_386_RELATIVE *0x%x = 0x%x + 0x%x\n", ptr, base, addend); - *ptr = base + addend; - break; +#ifdef SUPPORT_ELF64 +void *Elf64Relocate(void *Base, char **envp, const char *Filename) +{ + int i; + Elf64_Ehdr *hdr = Base; + Elf64_Phdr *phtab; + Elf64_Dyn *dyntab; + Elf64_Addr compiledBase = -1, baseDiff; + Elf64_Sym *symtab = NULL; + char *strtab = NULL; + Elf64_Word *hashtab = NULL; + Elf64_Rel *rel = NULL; + int rel_count = 0; + Elf64_Rela *rela = NULL; + int rela_count = 0; + void *pltrel = NULL; + int plt_size = 0, plt_type = 0; + + DEBUGS("Elf64Relocate: hdr = {"); + DEBUGS("Elf64Relocate: e_ident = '%.16s'", hdr->e_ident); + DEBUGS("Elf64Relocate: e_type = 0x%x", hdr->e_type); + DEBUGS("Elf64Relocate: e_machine = 0x%x", hdr->e_machine); + DEBUGS("Elf64Relocate: e_version = 0x%x", hdr->e_version); + DEBUGS("Elf64Relocate: e_entry = %p", hdr->e_entry); + DEBUGS("Elf64Relocate: e_phoff = 0x%llx", hdr->e_phoff); + DEBUGS("Elf64Relocate: e_shoff = 0x%llx", hdr->e_shoff); + DEBUGS("Elf64Relocate: e_flags = 0x%x", hdr->e_flags); + DEBUGS("Elf64Relocate: e_ehsize = 0x%x", hdr->e_ehsize); + DEBUGS("Elf64Relocate: e_phentsize = 0x%x", hdr->e_phentsize); + DEBUGS("Elf64Relocate: e_phnum = %i", hdr->e_phnum); + + // Scan for the dynamic table (and find the compiled base) + phtab = Base + hdr->e_phoff; + for( i = 0; i < hdr->e_phnum; i ++ ) + { + if(phtab[i].p_type == PT_DYNAMIC) + dyntab = (void *)(intptr_t)phtab[i].p_vaddr; + if(phtab[i].p_type == PT_LOAD && compiledBase > phtab[i].p_vaddr) + compiledBase = phtab[i].p_vaddr; + } + + baseDiff = (uintptr_t)Base - compiledBase; + + DEBUGS("baseDiff = %p", baseDiff); + + if(dyntab == NULL) { + SysDebug(" Elf64Relocate: No PT_DYNAMIC segment in image %p, returning", Base); + return (void *)(uintptr_t)(hdr->e_entry + baseDiff); + } + + dyntab = (void *)(uintptr_t)((uintptr_t)dyntab + baseDiff); + + // Parse the dynamic table (first pass) + // - Search for String, Symbol and Hash tables + for(i = 0; dyntab[i].d_tag != DT_NULL; i ++) + { + switch(dyntab[i].d_tag) + { + case DT_SYMTAB: + dyntab[i].d_un.d_ptr += baseDiff; + symtab = (void *)(uintptr_t)dyntab[i].d_un.d_ptr; + break; + case DT_STRTAB: + dyntab[i].d_un.d_ptr += baseDiff; + strtab = (void *)(uintptr_t)dyntab[i].d_un.d_ptr; + break; + case DT_HASH: + dyntab[i].d_un.d_ptr += baseDiff; + hashtab = (void *)(uintptr_t)dyntab[i].d_un.d_ptr; + break; + } + } + + if( !symtab || !strtab || !hashtab ) { + SysDebug("ld-acess - Elf64Relocate: Missing Symbol, string or hash table"); + return NULL; + } + + // Ready for symbol use + AddLoaded( Filename, Base ); + + // Second pass on dynamic table + for(i = 0; dyntab[i].d_tag != DT_NULL; i ++) + { + DEBUGS("dyntab[%i].d_tag = %i", i, dyntab[i].d_tag); + switch(dyntab[i].d_tag) + { + case DT_SONAME: break; + + case DT_NEEDED: { + char *libPath = strtab + dyntab[i].d_un.d_val; + DEBUGS("Elf64Relocate: libPath = '%s'", libPath); + if(LoadLibrary(libPath, NULL, envp) == 0) { + SysDebug("ld-acess - Elf64Relocate: Unable to load '%s'", libPath); + return NULL; + } + } break; - default: - DEBUGS(" elf_doRelocate: Rel 0x%x: 0x%x,%s\n", ptr, sym, csaR_NAMES[type]); - break; + // Relocation entries + case DT_REL: + dyntab[i].d_un.d_ptr += baseDiff; + rel = (void *)(uintptr_t)dyntab[i].d_un.d_ptr; + break; + case DT_RELSZ: + rel_count = dyntab[i].d_un.d_val / sizeof(Elf64_Rel); + break; + case DT_RELENT: + if( dyntab[i].d_un.d_val != sizeof(Elf64_Rel) ) { + SysDebug("ld-acess - Elf64Relocate: DT_RELENT(%i) != sizeof(Elf64_Rel)(%i)", + dyntab[i].d_un.d_val, sizeof(Elf64_Rel)); + return NULL; + } + break; + case DT_RELA: + dyntab[i].d_un.d_ptr += baseDiff; + rela = (void *)(uintptr_t)dyntab[i].d_un.d_ptr; + break; + case DT_RELASZ: + rela_count = dyntab[i].d_un.d_val / sizeof(Elf64_Rela); + break; + case DT_RELAENT: + if( dyntab[i].d_un.d_val != sizeof(Elf64_Rela) ) { + SysDebug("ld-acess - Elf64Relocate: DT_RELAENT(%i) != sizeof(Elf64_Rela)(%i)", + dyntab[i].d_un.d_val, sizeof(Elf64_Rela)); + return NULL; + } + break; + case DT_JMPREL: + dyntab[i].d_un.d_ptr += baseDiff; + pltrel = (void *)(uintptr_t)dyntab[i].d_un.d_ptr; + break; + case DT_PLTREL: + plt_type = dyntab[i].d_un.d_val; + break; + case DT_PLTRELSZ: + plt_size = dyntab[i].d_un.d_val; + break; + } + } + + // Relocation function + void _Elf64DoReloc(Elf64_Xword r_info, void *ptr, Elf64_Sxword addend) + { + int sym = ELF64_R_SYM(r_info); + int type = ELF64_R_TYPE(r_info); + const char *symname = strtab + symtab[sym].st_name; + switch( type ) + { + case R_X86_64_NONE: + break; + case R_X86_64_64: + *(uint64_t*)ptr = (uintptr_t)GetSymbol(symname, NULL) + addend; + break; + case R_X86_64_COPY: { + size_t size; + void *sym = GetSymbol(symname, &size); + memcpy(ptr, sym, size); + } break; + case R_X86_64_GLOB_DAT: + *(uint64_t*)ptr = (uintptr_t)GetSymbol(symname, NULL); + break; + case R_X86_64_JUMP_SLOT: + *(uint64_t*)ptr = (uintptr_t)GetSymbol(symname, NULL); + break; + case R_X86_64_RELATIVE: + *(uint64_t*)ptr = (uintptr_t)Base + addend; + break; + default: + SysDebug("ld-acess - _Elf64DoReloc: Unknown relocation type %i", type); + break; + } + } + + if( rel ) + { + DEBUGS("rel_count = %i", rel_count); + for( i = 0; i < rel_count; i ++ ) + { + uint64_t *ptr = (void *)(uintptr_t)( rel[i].r_offset + baseDiff ); + _Elf64DoReloc( rel[i].r_info, ptr, *ptr); + } + } + + if( rela ) + { + DEBUGS("rela_count = %i", rela_count); + for( i = 0; i < rela_count; i ++ ) + { + uint64_t *ptr = (void *)(uintptr_t)( rela[i].r_offset + baseDiff ); + _Elf64DoReloc( rela[i].r_info, ptr, rela[i].r_addend ); + } + } + + if( pltrel && plt_type ) + { + if( plt_type == DT_REL ) { + Elf64_Rel *plt = pltrel; + int count = plt_size / sizeof(Elf64_Rel); + DEBUGS("plt rel count = %i", count); + for( i = 0; i < count; i ++ ) + { + uint64_t *ptr = (void *)(uintptr_t)( plt[i].r_offset + baseDiff ); + _Elf64DoReloc( plt[i].r_info, ptr, *ptr); + } + } + else { + Elf64_Rela *plt = pltrel; + int count = plt_size / sizeof(Elf64_Rela); + DEBUGS("plt rela count = %i", count); + for( i = 0; i < count; i ++ ) + { + uint64_t *ptr = (void *)(uintptr_t)( plt[i].r_offset + baseDiff ); + _Elf64DoReloc( plt[i].r_info, ptr, plt[i].r_addend); + } + } + } + + { + void *ret = (void *)(uintptr_t)(hdr->e_entry + baseDiff); + DEBUGS("Elf64Relocate: Relocations done, return %p", ret); + return ret; } - } -/** - * \fn int ElfGetSymbol(Uint Base, char *name, void **ret) - */ -int ElfGetSymbol(void *Base, char *Name, void **ret) +int Elf64GetSymbol(void *Base, const char *Name, void **Ret, size_t *Size) { - Elf32_Ehdr *hdr = Base; - Elf32_Sym *symtab; + Elf64_Ehdr *hdr = Base; + Elf64_Sym *symtab; int nbuckets = 0; - int iSymCount = 0; +// int iSymCount = 0; int i; - Uint *pBuckets; - Uint *pChains; - Uint iNameHash; + Elf64_Word *pBuckets; + Elf64_Word *pChains; + uint32_t iNameHash; + const char *dynstrtab; + uintptr_t iBaseDiff = -1; - //DEBUGS("ElfGetSymbol: (Base=0x%x, Name='%s')\n", Base, Name); + dynstrtab = NULL; + pBuckets = NULL; + symtab = NULL; // Catch the current executable - #if 0 - if( !hdr->misc.HashTable ) + if( !pBuckets ) { - Elf32_Phdr *phtab; - Elf32_Dyn *dynTab = NULL; + Elf64_Phdr *phtab; + Elf64_Dyn *dynTab = NULL; int j; // Locate the tables - phtab = (void*)( Base + hdr->phoff ); - for( i = 0; i < hdr->phentcount; i ++ ) + phtab = (void*)( Base + hdr->e_phoff ); + for( i = 0; i < hdr->e_phnum; i ++ ) { - if( phtab[i].Type == PT_DYNAMIC ) { - dynTab = (void*)phtab[i].VAddr; - break ; + if(phtab[i].p_type == PT_LOAD && iBaseDiff > phtab[i].p_vaddr) + iBaseDiff = phtab[i].p_vaddr; + if( phtab[i].p_type == PT_DYNAMIC ) { + dynTab = (void*)(intptr_t)phtab[i].p_vaddr; } } if( !dynTab ) { - SysDebug("ERROR - Unable to find DYNAMIC segment in %p", (void*)Base); + SysDebug("ERROR - Unable to find DYNAMIC segment in %p", Base); return 0; } + iBaseDiff = (intptr_t)Base - iBaseDiff; // Make iBaseDiff actually the diff + dynTab = (void*)( (intptr_t)dynTab + iBaseDiff ); for( j = 0; dynTab[j].d_tag != DT_NULL; j++) { @@ -344,65 +767,59 @@ int ElfGetSymbol(void *Base, char *Name, void **ret) { // --- Symbol Table --- case DT_SYMTAB: - hdr->misc.SymTable = dynTab[j].d_val; + symtab = (void*)(intptr_t) dynTab[j].d_un.d_val; // Rebased in Relocate + break; + case DT_STRTAB: + dynstrtab = (void*)(intptr_t) dynTab[j].d_un.d_val; break; // --- Hash Table -- case DT_HASH: - hdr->misc.HashTable = dynTab[j].d_val; + pBuckets = (void*)(intptr_t) dynTab[j].d_un.d_val; break; } } } - #endif - - if( !hdr->misc.SymTable || !hdr->misc.HashTable ) { - return 0; - } - pBuckets = (void *) (intptr_t) hdr->misc.HashTable; - symtab = (void *) (intptr_t) hdr->misc.SymTable; - nbuckets = pBuckets[0]; - iSymCount = pBuckets[1]; +// iSymCount = pBuckets[1]; pBuckets = &pBuckets[2]; pChains = &pBuckets[ nbuckets ]; // Get hash iNameHash = ElfHashString(Name); iNameHash %= nbuckets; - //DEBUGS(" ElfGetSymbol: iNameHash = 0x%x\n", iNameHash); // Walk Chain i = pBuckets[ iNameHash ]; - //DEBUGS(" ElfGetSymbol: strcmp(Name, \"%s\")\n", symtab[i].name); - if(symtab[i].shndx != SHN_UNDEF && strcmp(symtab[i].name, Name) == 0) { - *ret = (void*) (intptr_t) symtab[ i ].value; + if(symtab[i].st_shndx != SHN_UNDEF && strcmp(dynstrtab + symtab[i].st_name, Name) == 0) { + *Ret = (void*) (intptr_t) symtab[i].st_value + iBaseDiff; + if(Size) *Size = symtab[i].st_size; + DEBUGS("%s = %p", Name, *Ret); return 1; } - //DEBUGS(" ElfGetSymbol: Hash of first = 0x%x\n", ElfHashString( symtab[i].name ) % nbuckets); while(pChains[i] != STN_UNDEF) { - //DEBUGS(" pChains[%i] = %i\n", i, pChains[i]); i = pChains[i]; - //DEBUGS(" ElfGetSymbol: strcmp(Name, \"%s\")\n", symtab[ i ].name); - if(symtab[i].shndx != SHN_UNDEF && strcmp(symtab[ i ].name, Name) == 0) { - //DEBUGS("ElfGetSymbol: RETURN 1, '%s' = 0x%x\n", symtab[ i ].name, symtab[ i ].value); - *ret = (void*)(intptr_t)symtab[ i ].value; + if(symtab[i].st_shndx != SHN_UNDEF && strcmp(dynstrtab + symtab[i].st_name, Name) == 0) { + *Ret = (void*)(intptr_t)symtab[i].st_value + iBaseDiff; + if(Size) *Size = symtab[i].st_size; + DEBUGS("%s = %p", Name, *Ret); return 1; } } - //DEBUGS("ElfGetSymbol: RETURN 0, Symbol '%s' not found\n", Name); return 0; } +#endif -Uint ElfHashString(char *name) + +uint32_t ElfHashString(const char *name) { - Uint h = 0, g; + uint32_t h = 0, g; while(*name) { - h = (h << 4) + *name++; + h = (h << 4) + *(uint8_t*)name++; if( (g = h & 0xf0000000) ) h ^= g >> 24; h &= ~g; @@ -410,17 +827,3 @@ Uint ElfHashString(char *name) return h; } -#if 0 -unsigned long elf_hash(const unsigned char *name) -{ - unsigned long h = 0, g; - while (*name) - { - h = (h << 4) + *name++; - if (g = h & 0xf0000000) - h ^= g >> 24; - h &= ~g; - } - return h; -} -#endif