* 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 <stdint.h>
# define DEBUGS(...)
#endif
-//#if BITS > 32
+#ifndef DISABLE_ELF64
# define SUPPORT_ELF64
-//#endif
+#endif
// === CONSTANTS ===
#if DEBUG
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);
}
}
+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_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);
// Parse Program Header to get Dynamic Table
- phtab = Base + hdr->phoff;
+ phtab = (void*)( (uintptr_t)Base + hdr->phoff );
iSegmentCount = hdr->phentcount;
for(i=0;i<iSegmentCount;i++)
{
}
DEBUGS(" elf_relocate: Beginning Relocation");
-
- void elf_doRelocate_386(uint32_t r_info, uint32_t *ptr, Elf32_Addr addend, int type, int bRela, const char *Sym)
- {
- 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)
- {
- 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 _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);
+ 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)
{
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)
}
}
+ 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;
// 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;
}
{
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;
}
int i;
Elf64_Ehdr *hdr = Base;
Elf64_Phdr *phtab;
- Elf64_Dyn *dyntab;
+ Elf64_Dyn *dyntab = NULL;
Elf64_Addr compiledBase = -1, baseDiff;
Elf64_Sym *symtab = NULL;
char *strtab = NULL;
DEBUGS("Elf64Relocate: e_phnum = %i", hdr->e_phnum);
// Scan for the dynamic table (and find the compiled base)
- phtab = 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)
break;
case R_X86_64_COPY: {
size_t size;
- void *sym = GetSymbol(symname, &size);
- memcpy(ptr, sym, size);
+ void *symptr = GetSymbol(symname, &size);
+ memcpy(ptr, symptr, size);
} break;
case R_X86_64_GLOB_DAT:
*(uint64_t*)ptr = (uintptr_t)GetSymbol(symname, NULL);
int j;
// Locate the tables
- phtab = (void*)( 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)
// 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;
{
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;
git.ucc.asn.au / tpg / acess2.git / blobdiff
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