X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Usermode%2FLibraries%2Fld-acess.so_src%2Felf.c;h=4a87896d68e2c44c4328c317fe117af8841e5bb6;hb=ea8e0fad3dfc8bf735d41eedbad2a8e6198059aa;hp=4b081bcbe20c16a85ee3cc062e24c19603ddedf8;hpb=b7f014bb53b817944bb14640ebf8cfc755d4ce56;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 4b081bcb..4a87896d 100644 --- a/Usermode/Libraries/ld-acess.so_src/elf.c +++ b/Usermode/Libraries/ld-acess.so_src/elf.c @@ -9,6 +9,10 @@ # define DEBUG 0 #endif +#ifndef PAGE_SIZE +# define PAGE_SIZE 4096 +#endif + #include "common.h" #include #include "elf32.h" @@ -35,8 +39,8 @@ 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); + int elf_doRelocate_386(uint32_t r_info, uint32_t *ptr, Elf32_Addr addend, int type, int bRela, const char *Sym, intptr_t iBaseDiff); + int 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); @@ -87,26 +91,28 @@ 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) +int 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; + void *symval; 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; + if( !GetSymbol(Sym, &symval, NULL) ) + return 1; + DEBUGS(" elf_doRelocate: R_386_32 *0x%x += %p('%s')", + ptr, symval, Sym); + *ptr = (intptr_t)symval + 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; + if( !GetSymbol(Sym, &symval, NULL) ) return 1; + DEBUGS(" elf_doRelocate: R_386_PC32 *0x%x = 0x%x + 0x%p - 0x%x", + ptr, *ptr, symval, (intptr_t)ptr ); + *ptr = (intptr_t)symval + addend - (intptr_t)ptr; //*ptr = val + addend - ((Uint)ptr - iBaseDiff); break; @@ -114,9 +120,9 @@ void elf_doRelocate_386(uint32_t r_info, uint32_t *ptr, Elf32_Addr addend, int t 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; + if( !GetSymbol(Sym, &symval, NULL) ) return 1; + DEBUGS(" elf_doRelocate: %s *0x%x = %p", csaR_NAMES[type], ptr, symval); + *ptr = (intptr_t)symval; break; // Base Address (B+A) @@ -127,18 +133,19 @@ void elf_doRelocate_386(uint32_t r_info, uint32_t *ptr, Elf32_Addr addend, int t 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); + if( !GetSymbol(Sym, &symval, &size) ) return 1; + DEBUGS(" elf_doRelocate_386: R_386_COPY (%p, %p, %i)", ptr, symval, size); + memcpy(ptr, symval, size); break; } default: SysDebug("elf_doRelocate_386: Unknown relocation %i", type); - break; + return 2; } + return 0; } -void elf_doRelocate_arm(uint32_t r_info, uint32_t *ptr, Elf32_Addr addend, int type, int bRela, const char *Sym, intptr_t iBaseDiff) +int 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) @@ -146,32 +153,35 @@ void elf_doRelocate_arm(uint32_t r_info, uint32_t *ptr, Elf32_Addr addend, int t // (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); + if( !GetSymbol(Sym, (void**)&val, NULL) ) return 1; *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); + if( !GetSymbol(Sym, (void**)&val, NULL) ) return 1; *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); + if( !GetSymbol(Sym, (void**)&val, NULL) ) return 1; *ptr = val + addend; break; // Copy case R_ARM_COPY: { size_t size; - void *src = GetSymbol(Sym, &size); + void *src; + if( !GetSymbol(Sym, &src, &size) ) return 1; 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: + DEBUGS(" elf_doRelocate_arm: R_ARM_RELATIVE %p (0x%x + 0x%x)", ptr, iBaseDiff, addend); if(Sym[0] != '\0') { // TODO: Get delta for a symbol SysDebug("elf_doRelocate_arm: TODO - Implment R_ARM_RELATIVE for symbols"); + return 2; } else { *ptr = iBaseDiff + addend; @@ -179,8 +189,9 @@ void elf_doRelocate_arm(uint32_t r_info, uint32_t *ptr, Elf32_Addr addend, int t break; default: SysDebug("elf_doRelocate_arm: Unknown Relocation, %i", type); - break; + return 2; } + return 0; } void *Elf32Relocate(void *Base, char **envp, const char *Filename) @@ -202,8 +213,7 @@ 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, intptr_t iBaseDiff); - auto void _doRelocate(uint32_t r_info, uint32_t *ptr, int bRela, Elf32_Addr addend); + int (*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)", Base); @@ -236,7 +246,7 @@ void *Elf32Relocate(void *Base, char **envp, const char *Filename) // Adjust "Real" Base iBaseDiff = (intptr_t)Base - iRealBase; - + // hdr->entrypoint += iBaseDiff; // Adjust Entrypoint // Check if a PT_DYNAMIC segement was found @@ -244,7 +254,19 @@ void *Elf32Relocate(void *Base, char **envp, const char *Filename) SysDebug(" elf_relocate: No PT_DYNAMIC segment in image %p, returning", Base); return (void *)(intptr_t)(hdr->entrypoint + iBaseDiff); } - + + // Allow writing to read-only segments, just in case they need to be relocated + // - Will be reversed at the end of the function + for( i = 0; i < iSegmentCount; i ++ ) + { + if(phtab[i].Type == PT_LOAD && !(phtab[i].Flags & PF_W) ) { + uintptr_t addr = phtab[i].VAddr + iBaseDiff; + uintptr_t end = addr + phtab[i].MemSize; + for( ; addr < end; addr += PAGE_SIZE ) + SysSetMemFlags(addr, 0, 1); // Unset RO + } + } + // Adjust Dynamic Table dynamicTab = (void *)( (intptr_t)dynamicTab + iBaseDiff ); @@ -340,14 +362,6 @@ void *Elf32Relocate(void *Base, char **envp, const char *Filename) 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: @@ -358,11 +372,18 @@ void *Elf32Relocate(void *Base, char **envp, const char *Filename) break; default: SysDebug("Elf32Relocate: Unknown machine type %i", hdr->machine); + // TODO: Chuck sad break; } DEBUGS("do_relocate = %p (%p or %p)", do_relocate, &elf_doRelocate_386, &elf_doRelocate_arm); + int fail = 0; + + #define _doRelocate(r_info, ptr, bRela, addend) \ + do_relocate(r_info, ptr, addend, ELF32_R_TYPE(r_info), bRela, \ + dynstrtab + dynsymtab[ELF32_R_SYM(r_info)].nameOfs, iBaseDiff); + // Parse Relocation Entries if(rel && relSz) { @@ -373,7 +394,7 @@ void *Elf32Relocate(void *Base, char **envp, const char *Filename) { //DEBUGS(" Rel %i: 0x%x+0x%x", i, iBaseDiff, rel[i].r_offset); ptr = (void*)(iBaseDiff + rel[i].r_offset); - _doRelocate(rel[i].r_info, ptr, 0, *ptr); + fail |= _doRelocate(rel[i].r_info, ptr, 0, *ptr); } } // Parse Relocation Entries @@ -385,7 +406,7 @@ void *Elf32Relocate(void *Base, char **envp, const char *Filename) for( i = 0; i < j; i++ ) { ptr = (void*)(iBaseDiff + rela[i].r_offset); - _doRelocate(rel[i].r_info, ptr, 1, rela[i].r_addend); + fail |= _doRelocate(rel[i].r_info, ptr, 1, rela[i].r_addend); } } @@ -402,7 +423,7 @@ void *Elf32Relocate(void *Base, char **envp, const char *Filename) for(i=0;ientrypoint + iBaseDiff, __builtin_return_address(0)); return (void*)(intptr_t)( hdr->entrypoint + iBaseDiff ); } @@ -554,7 +594,7 @@ void *Elf64Relocate(void *Base, char **envp, const char *Filename) DEBUGS("Elf64Relocate: e_phnum = %i", hdr->e_phnum); // Scan for the dynamic table (and find the compiled base) - phtab = (void*)((uintptr_t)Base + hdr->e_phoff); + phtab = (void*)((uintptr_t)Base + (uintptr_t)hdr->e_phoff); for( i = 0; i < hdr->e_phnum; i ++ ) { if(phtab[i].p_type == PT_DYNAMIC) @@ -663,45 +703,54 @@ void *Elf64Relocate(void *Base, char **envp, const char *Filename) } // Relocation function - void _Elf64DoReloc(Elf64_Xword r_info, void *ptr, Elf64_Sxword addend) + auto int _Elf64DoReloc(Elf64_Xword r_info, void *ptr, Elf64_Sxword addend); + int _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; + void *symval; + //DEBUGS("_Elf64DoReloc: %s", symname); switch( type ) { case R_X86_64_NONE: break; case R_X86_64_64: - *(uint64_t*)ptr = (uintptr_t)GetSymbol(symname, NULL) + addend; + if( !GetSymbol(symname, &symval, NULL) ) return 1; + *(uint64_t*)ptr = (uintptr_t)symval + addend; break; case R_X86_64_COPY: { size_t size; - void *symptr = GetSymbol(symname, &size); - memcpy(ptr, symptr, size); + if( !GetSymbol(symname, &symval, &size) ) return 1; + memcpy(ptr, symval, size); } break; case R_X86_64_GLOB_DAT: - *(uint64_t*)ptr = (uintptr_t)GetSymbol(symname, NULL); + if( !GetSymbol(symname, &symval, NULL) ) return 1; + *(uint64_t*)ptr = (uintptr_t)symval; break; case R_X86_64_JUMP_SLOT: - *(uint64_t*)ptr = (uintptr_t)GetSymbol(symname, NULL); + if( !GetSymbol(symname, &symval, NULL) ) return 1; + *(uint64_t*)ptr = (uintptr_t)symval; 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; + return 2; } + //DEBUGS("_Elf64DoReloc: - Good"); + return 0; } + int fail = 0; 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); + fail |= _Elf64DoReloc( rel[i].r_info, ptr, *ptr); } } @@ -711,7 +760,7 @@ void *Elf64Relocate(void *Base, char **envp, const char *Filename) 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 ); + fail |= _Elf64DoReloc( rela[i].r_info, ptr, rela[i].r_addend ); } } @@ -724,7 +773,7 @@ void *Elf64Relocate(void *Base, char **envp, const char *Filename) for( i = 0; i < count; i ++ ) { uint64_t *ptr = (void *)(uintptr_t)( plt[i].r_offset + baseDiff ); - _Elf64DoReloc( plt[i].r_info, ptr, *ptr); + fail |= _Elf64DoReloc( plt[i].r_info, ptr, *ptr); } } else { @@ -734,11 +783,16 @@ void *Elf64Relocate(void *Base, char **envp, const char *Filename) 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); + fail |= _Elf64DoReloc( plt[i].r_info, ptr, plt[i].r_addend); } } } + if( fail ) { + DEBUGS("Elf64Relocate: Failure"); + return NULL; + } + { void *ret = (void *)(uintptr_t)(hdr->e_entry + baseDiff); DEBUGS("Elf64Relocate: Relocations done, return %p", ret); @@ -771,7 +825,7 @@ int Elf64GetSymbol(void *Base, const char *Name, void **Ret, size_t *Size) int j; // Locate the tables - phtab = (void*)( (intptr_t)Base + hdr->e_phoff ); + phtab = (void*)( (intptr_t)Base + (uintptr_t)hdr->e_phoff ); for( i = 0; i < hdr->e_phnum; i ++ ) { if(phtab[i].p_type == PT_LOAD && iBaseDiff > phtab[i].p_vaddr)