X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Usermode%2FLibraries%2Fld-acess.so_src%2Felf.c;h=92237eaa3d487c1995c0478e0b46225f1c7a9c8c;hb=11dbd684e9a3d907d43d71a3145205f1a86992fb;hp=0877c2299b676ea07d7fb3b52e3309186405ad70;hpb=02907f27e675b13565f61708d981c9e3511c2764;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 0877c229..92237eaa 100644 --- a/Usermode/Libraries/ld-acess.so_src/elf.c +++ b/Usermode/Libraries/ld-acess.so_src/elf.c @@ -5,7 +5,9 @@ * elf.c * - ELF32/ELF64 relocation */ -#define DEBUG 0 +#ifndef DEBUG // This code is #include'd from the kernel, so DEBUG may already be defined +# define DEBUG 0 +#endif #include "common.h" #include @@ -18,9 +20,9 @@ # define DEBUGS(...) #endif -//#if BITS > 32 +#ifndef DISABLE_ELF64 # define SUPPORT_ELF64 -//#endif +#endif // === CONSTANTS === #if DEBUG @@ -33,6 +35,8 @@ 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); +void elf_doRelocate_386(uint32_t r_info, uint32_t *ptr, Elf32_Addr addend, int type, int bRela, const char *Sym, intptr_t iBaseDiff); +void elf_doRelocate_arm(uint32_t r_info, uint32_t *ptr, Elf32_Addr addend, int type, int bRela, const char *Sym, intptr_t iBaseDiff); #ifdef SUPPORT_ELF64 void *Elf64Relocate(void *Base, char **envp, const char *Filename); int Elf64GetSymbol(void *Base, const char *Name, void **Ret, size_t *Size); @@ -83,6 +87,102 @@ int ElfGetSymbol(void *Base, const char *Name, void **ret, size_t *Size) } } +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; @@ -102,7 +202,8 @@ void *Elf32Relocate(void *Base, char **envp, const 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); + void (*do_relocate)(uint32_t t_info, uint32_t *ptr, Elf32_Addr addend, int Type, int bRela, const char *Sym, intptr_t iBaseDiff); + auto void _doRelocate(uint32_t r_info, uint32_t *ptr, int bRela, Elf32_Addr addend); DEBUGS("ElfRelocate: (Base=0x%x)", Base); @@ -110,7 +211,7 @@ void *Elf32Relocate(void *Base, char **envp, const char *Filename) // Parse Program Header to get Dynamic Table - phtab = Base + hdr->phoff; + phtab = (void*)( (uintptr_t)Base + hdr->phoff ); iSegmentCount = hdr->phentcount; for(i=0;imachine) @@ -334,6 +361,8 @@ void *Elf32Relocate(void *Base, char **envp, const char *Filename) break; } + DEBUGS("do_relocate = %p (%p or %p)", do_relocate, &elf_doRelocate_386, &elf_doRelocate_arm); + // Parse Relocation Entries if(rel && relSz) { @@ -396,20 +425,19 @@ void *Elf32Relocate(void *Base, char **envp, const char *Filename) int Elf32GetSymbol(void *Base, const char *Name, void **ret, size_t *Size) { Elf32_Ehdr *hdr = Base; - Elf32_Sym *symtab; + Elf32_Sym *symtab = NULL; int nbuckets = 0; -// int iSymCount = 0; - int i; - Elf32_Word *pBuckets; + Elf32_Word *pBuckets = NULL; Elf32_Word *pChains; uint32_t iNameHash; - const char *dynstrtab; + const char *dynstrtab = NULL; uintptr_t iBaseDiff = -1; Elf32_Phdr *phtab; Elf32_Dyn *dynTab = NULL; + int i; // Locate the tables - phtab = (void*)( Base + hdr->phoff ); + phtab = (void*)( (uintptr_t)Base + hdr->phoff ); for( i = 0; i < hdr->phentcount; i ++ ) { if(phtab[i].Type == PT_LOAD && iBaseDiff > phtab[i].VAddr) @@ -442,11 +470,33 @@ int Elf32GetSymbol(void *Base, const char *Name, void **ret, size_t *Size) } } + if( !symtab ) { + SysDebug("ERRO - No DT_SYMTAB in %p", Base); + return 0; + } + if( !pBuckets ) { + SysDebug("ERRO - No DT_HASH in %p", Base); + return 0; + } + if( !dynstrtab ) { + SysDebug("ERRO - No DT_STRTAB in %p", Base); + return 0; + } + + // ... ok... maybe they haven't been relocated + if( (uintptr_t)symtab < (uintptr_t)Base ) + { + symtab = (void*)( (uintptr_t)symtab + iBaseDiff ); + pBuckets = (void*)( (uintptr_t)pBuckets + iBaseDiff ); + dynstrtab = (void*)( (uintptr_t)dynstrtab + iBaseDiff ); + SysDebug("Executable not yet relocated"); + } + nbuckets = pBuckets[0]; // iSymCount = pBuckets[1]; pBuckets = &pBuckets[2]; pChains = &pBuckets[ nbuckets ]; - + // Get hash iNameHash = ElfHashString(Name); iNameHash %= nbuckets; @@ -454,7 +504,7 @@ int Elf32GetSymbol(void *Base, const char *Name, void **ret, size_t *Size) // 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; + *ret = (void*)( (uintptr_t) symtab[ i ].value + iBaseDiff ); if(Size) *Size = symtab[i].size; return 1; } @@ -463,7 +513,7 @@ int Elf32GetSymbol(void *Base, const char *Name, void **ret, size_t *Size) { i = pChains[i]; if(symtab[i].shndx != SHN_UNDEF && strcmp(dynstrtab + symtab[ i ].nameOfs, Name) == 0) { - *ret = (void*)(intptr_t)symtab[ i ].value + iBaseDiff; + *ret = (void*)( (uintptr_t)symtab[ i ].value + iBaseDiff ); if(Size) *Size = symtab[i].size; return 1; } @@ -721,7 +771,7 @@ int Elf64GetSymbol(void *Base, const char *Name, void **Ret, size_t *Size) int j; // Locate the tables - phtab = (void*)( Base + hdr->e_phoff ); + phtab = (void*)( (intptr_t)Base + hdr->e_phoff ); for( i = 0; i < hdr->e_phnum; i ++ ) { if(phtab[i].p_type == PT_LOAD && iBaseDiff > phtab[i].p_vaddr) @@ -768,7 +818,7 @@ int Elf64GetSymbol(void *Base, const char *Name, void **Ret, size_t *Size) // Walk Chain i = pBuckets[ iNameHash ]; if(symtab[i].st_shndx != SHN_UNDEF && strcmp(dynstrtab + symtab[i].st_name, Name) == 0) { - *Ret = (void*) (intptr_t) symtab[i].st_value + iBaseDiff; + *Ret = (void*)( (intptr_t)symtab[i].st_value + iBaseDiff ); if(Size) *Size = symtab[i].st_size; DEBUGS("%s = %p", Name, *Ret); return 1; @@ -778,7 +828,7 @@ int Elf64GetSymbol(void *Base, const char *Name, void **Ret, size_t *Size) { i = pChains[i]; if(symtab[i].st_shndx != SHN_UNDEF && strcmp(dynstrtab + symtab[i].st_name, Name) == 0) { - *Ret = (void*)(intptr_t)symtab[i].st_value + iBaseDiff; + *Ret = (void*)((intptr_t)symtab[i].st_value + iBaseDiff); if(Size) *Size = symtab[i].st_size; DEBUGS("%s = %p", Name, *Ret); return 1;