/*
- * 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 <stdint.h>
#include "elf32.h"
#include "elf64.h"
-#define DEBUG 0
-
#if DEBUG
# define DEBUGS(v...) SysDebug("ld-acess - " v)
#else
void *Elf64Relocate(void *Base, char **envp, const char *Filename);
int Elf64GetSymbol(void *Base, const char *Name, void **Ret, size_t *Size);
#endif
-Uint32 ElfHashString(const char *name);
+uint32_t ElfHashString(const char *name);
// === CODE ===
/**
}
}
+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;
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;
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, 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);
DEBUGS("ElfRelocate: (Base=0x%x)", Base);
// --- Hash Table --
case DT_HASH:
if(iBaseDiff != 0) dynamicTab[j].d_val += iBaseDiff;
- iSymCount = ((Elf32_Word*)(intptr_t)dynamicTab[j].d_val)[1];
+// iSymCount = ((Elf32_Word*)(intptr_t)dynamicTab[j].d_val)[1];
break;
}
}
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;
}
DEBUGS(" elf_relocate: Beginning Relocation");
-
- void elf_doRelocate_386(uint32_t r_info, uint32_t *ptr, Elf32_Addr addend, int type, const char *Sym)
- {
- Uint32 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, val, 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, const char *Sym)
- {
- uint32_t val;
- switch(type)
- {
- // (S + A) | T
- case R_ARM_GLOB_DAT:
- case R_ARM_JUMP_SLOT:
- val = (intptr_t)GetSymbol(Sym, NULL);
- *ptr = val + addend;
- break;
- default:
- SysDebug("elf_doRelocate_arm: Unknown Relocation, %i", type);
- break;
- }
- }
- void _doRelocate(uint32_t r_info, uint32_t *ptr, Elf32_Addr addend)
+ 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, symname);
+ do_relocate(r_info, ptr, addend, type, bRela, symname, iBaseDiff);
}
switch(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;
+ 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", i, iBaseDiff, rel[i].r_offset);
ptr = (void*)(iBaseDiff + rel[i].r_offset);
- _doRelocate(rel[i].r_info, ptr, *ptr);
+ _doRelocate(rel[i].r_info, ptr, 0, *ptr);
}
}
// Parse Relocation Entries
if(rela && relaSz)
{
- Uint32 *ptr;
+ 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);
- _doRelocate(rel[i].r_info, ptr, rela[i].r_addend);
+ _doRelocate(rel[i].r_info, ptr, 1, rela[i].r_addend);
}
}
// === Process PLT (Procedure Linkage Table) ===
if(plt && pltSz)
{
- Uint32 *ptr;
+ Elf32_Word *ptr;
DEBUGS(" elf_relocate: Relocate PLT, plt=0x%x", plt);
if(pltType == DT_REL)
{
for(i=0;i<j;i++)
{
ptr = (void*)(iBaseDiff + pltRel[i].r_offset);
- _doRelocate(pltRel[i].r_info, ptr, *ptr);
+ _doRelocate(pltRel[i].r_info, ptr, 0, *ptr);
}
}
else
for(i=0;i<j;i++)
{
ptr = (void*)(iRealBase + pltRela[i].r_offset);
- _doRelocate(pltRela[i].r_info, ptr, pltRela[i].r_addend);
+ _doRelocate(pltRela[i].r_info, ptr, 1, pltRela[i].r_addend);
}
}
}
- DEBUGS("ElfRelocate: RETURN 0x%x", hdr->entrypoint + iBaseDiff);
+ DEBUGS("ElfRelocate: RETURN 0x%x to %p", hdr->entrypoint + iBaseDiff, __builtin_return_address(0));
return (void*)(intptr_t)( hdr->entrypoint + iBaseDiff );
}
Elf32_Ehdr *hdr = Base;
Elf32_Sym *symtab;
int nbuckets = 0;
- int iSymCount = 0;
+// int iSymCount = 0;
int i;
- Uint32 *pBuckets;
- Uint32 *pChains;
+ Elf32_Word *pBuckets;
+ Elf32_Word *pChains;
uint32_t iNameHash;
const char *dynstrtab;
uintptr_t iBaseDiff = -1;
}
nbuckets = pBuckets[0];
- iSymCount = pBuckets[1];
+// iSymCount = pBuckets[1];
pBuckets = &pBuckets[2];
pChains = &pBuckets[ nbuckets ];
compiledBase = phtab[i].p_vaddr;
}
- baseDiff = (Elf64_Addr)Base - compiledBase;
+ 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 *)(hdr->e_entry + baseDiff);
+ return (void *)(uintptr_t)(hdr->e_entry + baseDiff);
}
- dyntab = (void *)((Elf64_Addr)dyntab + baseDiff);
+ dyntab = (void *)(uintptr_t)((uintptr_t)dyntab + baseDiff);
// Parse the dynamic table (first pass)
// - Search for String, Symbol and Hash tables
{
case DT_SYMTAB:
dyntab[i].d_un.d_ptr += baseDiff;
- symtab = (void *)dyntab[i].d_un.d_ptr;
+ symtab = (void *)(uintptr_t)dyntab[i].d_un.d_ptr;
break;
case DT_STRTAB:
dyntab[i].d_un.d_ptr += baseDiff;
- strtab = (void *)dyntab[i].d_un.d_ptr;
+ strtab = (void *)(uintptr_t)dyntab[i].d_un.d_ptr;
break;
case DT_HASH:
dyntab[i].d_un.d_ptr += baseDiff;
- hashtab = (void *)dyntab[i].d_un.d_ptr;
+ hashtab = (void *)(uintptr_t)dyntab[i].d_un.d_ptr;
break;
}
}
// Relocation entries
case DT_REL:
dyntab[i].d_un.d_ptr += baseDiff;
- rel = (void *)dyntab[i].d_un.d_ptr;
+ 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_RELA:
dyntab[i].d_un.d_ptr += baseDiff;
- rela = (void *)dyntab[i].d_un.d_ptr;
+ 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_JMPREL:
dyntab[i].d_un.d_ptr += baseDiff;
- pltrel = (void *)dyntab[i].d_un.d_ptr;
+ pltrel = (void *)(uintptr_t)dyntab[i].d_un.d_ptr;
break;
case DT_PLTREL:
plt_type = dyntab[i].d_un.d_val;
case R_X86_64_NONE:
break;
case R_X86_64_64:
- *(uint64_t*)ptr = (uint64_t)GetSymbol(symname, NULL) + addend;
+ *(uint64_t*)ptr = (uintptr_t)GetSymbol(symname, NULL) + addend;
break;
case R_X86_64_COPY: {
size_t size;
memcpy(ptr, sym, size);
} break;
case R_X86_64_GLOB_DAT:
- *(uint64_t*)ptr = (uint64_t)GetSymbol(symname, NULL);
+ *(uint64_t*)ptr = (uintptr_t)GetSymbol(symname, NULL);
break;
case R_X86_64_JUMP_SLOT:
- *(uint64_t*)ptr = (uint64_t)GetSymbol(symname, NULL);
+ *(uint64_t*)ptr = (uintptr_t)GetSymbol(symname, NULL);
break;
case R_X86_64_RELATIVE:
- *(uint64_t*)ptr = (intptr_t)Base + addend;
+ *(uint64_t*)ptr = (uintptr_t)Base + addend;
break;
default:
SysDebug("ld-acess - _Elf64DoReloc: Unknown relocation type %i", type);
DEBUGS("rel_count = %i", rel_count);
for( i = 0; i < rel_count; i ++ )
{
- uint64_t *ptr = (void *)( rel[i].r_offset + baseDiff );
+ uint64_t *ptr = (void *)(uintptr_t)( rel[i].r_offset + baseDiff );
_Elf64DoReloc( rel[i].r_info, ptr, *ptr);
}
}
DEBUGS("rela_count = %i", rela_count);
for( i = 0; i < rela_count; i ++ )
{
- _Elf64DoReloc( rela[i].r_info, (void *)( rela[i].r_offset + baseDiff ), rela[i].r_addend );
+ uint64_t *ptr = (void *)(uintptr_t)( rela[i].r_offset + baseDiff );
+ _Elf64DoReloc( rela[i].r_info, ptr, rela[i].r_addend );
}
}
DEBUGS("plt rel count = %i", count);
for( i = 0; i < count; i ++ )
{
- uint64_t *ptr = (void *)( plt[i].r_offset + baseDiff );
+ uint64_t *ptr = (void *)(uintptr_t)( plt[i].r_offset + baseDiff );
_Elf64DoReloc( plt[i].r_info, ptr, *ptr);
}
}
DEBUGS("plt rela count = %i", count);
for( i = 0; i < count; i ++ )
{
- _Elf64DoReloc( plt[i].r_info, (void *)(plt[i].r_offset + baseDiff), plt[i].r_addend);
+ uint64_t *ptr = (void *)(uintptr_t)( plt[i].r_offset + baseDiff );
+ _Elf64DoReloc( plt[i].r_info, ptr, plt[i].r_addend);
}
}
}
- DEBUGS("Elf64Relocate: Relocations done, return %p", (void *)(hdr->e_entry + baseDiff));
- return (void *)(hdr->e_entry + baseDiff);
+ {
+ void *ret = (void *)(uintptr_t)(hdr->e_entry + baseDiff);
+ DEBUGS("Elf64Relocate: Relocations done, return %p", ret);
+ return ret;
+ }
}
int Elf64GetSymbol(void *Base, const char *Name, void **Ret, size_t *Size)
Elf64_Ehdr *hdr = Base;
Elf64_Sym *symtab;
int nbuckets = 0;
- int iSymCount = 0;
+// int iSymCount = 0;
int i;
Elf64_Word *pBuckets;
Elf64_Word *pChains;
}
nbuckets = pBuckets[0];
- iSymCount = pBuckets[1];
+// iSymCount = pBuckets[1];
pBuckets = &pBuckets[2];
pChains = &pBuckets[ nbuckets ];
#endif
-Uint32 ElfHashString(const char *name)
+uint32_t ElfHashString(const char *name)
{
- Uint32 h = 0, g;
+ uint32_t h = 0, g;
while(*name)
{
- h = (h << 4) + *(Uint8*)name++;
+ h = (h << 4) + *(uint8_t*)name++;
if( (g = h & 0xf0000000) )
h ^= g >> 24;
h &= ~g;