Usermode/ld-acess - Fixes for clang compilation
[tpg/acess2.git] / Usermode / Libraries / ld-acess.so_src / elf.c
index 92237ea..531b32d 100644 (file)
@@ -9,6 +9,10 @@
 # define DEBUG 0
 #endif
 
+#ifndef PAGE_SIZE
+# define PAGE_SIZE     4096
+#endif
+
 #include "common.h"
 #include <stdint.h>
 #include "elf32.h"
@@ -35,8 +39,9 @@ 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);
+ int   elf_doRelocate_unk(uint32_t , uint32_t *, Elf32_Addr , int , int , const char *, intptr_t);
 #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 +92,28 @@ 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 +121,9 @@ 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 +134,19 @@ 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 +154,35 @@ 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 +190,14 @@ 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;
+}
+
+int elf_doRelocate_unk(uint32_t r_info, uint32_t *ptr, Elf32_Addr addend, int type, int bRela, const char *Sym, intptr_t iBaseDiff)
+{
+       return 1;
 }
 
 void *Elf32Relocate(void *Base, char **envp, const char *Filename)
@@ -202,8 +219,7 @@ 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 +252,7 @@ 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
@@ -244,11 +260,24 @@ 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 );
        
        // === Get Symbol table and String Table ===
+       dynsymtab = NULL;
        for( j = 0; dynamicTab[j].d_tag != DT_NULL; j++)
        {
                switch(dynamicTab[j].d_tag)
@@ -340,13 +369,7 @@ 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);
-       }
+        int    fail = 0;
 
        switch(hdr->machine)
        {
@@ -358,11 +381,17 @@ void *Elf32Relocate(void *Base, char **envp, const char *Filename)
                break;
        default:
                SysDebug("Elf32Relocate: Unknown machine type %i", hdr->machine);
+               do_relocate = elf_doRelocate_unk;
+               fail = 1;
                break;
        }
        
        DEBUGS("do_relocate = %p (%p or %p)", do_relocate, &elf_doRelocate_386, &elf_doRelocate_arm);
 
+       #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 +402,7 @@ 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 +414,7 @@ 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 +431,7 @@ void *Elf32Relocate(void *Base, char **envp, const char *Filename)
                        for(i=0;i<j;i++)
                        {
                                ptr = (void*)(iBaseDiff + pltRel[i].r_offset);
-                               _doRelocate(pltRel[i].r_info, ptr, 0, *ptr);
+                               fail |= _doRelocate(pltRel[i].r_info, ptr, 0, *ptr);
                        }
                }
                else
@@ -413,11 +442,30 @@ void *Elf32Relocate(void *Base, char **envp, const char *Filename)
                        for(i=0;i<j;i++)
                        {
                                ptr = (void*)(iRealBase + pltRela[i].r_offset);
-                               _doRelocate(pltRela[i].r_info, ptr, 1, pltRela[i].r_addend);
+                               fail |= _doRelocate(pltRela[i].r_info, ptr, 1, pltRela[i].r_addend);
                        }
                }
        }
-       
+
+       // Re-set readonly
+       for( i = 0; i < iSegmentCount; i ++ )
+       {
+               // If load and not writable
+               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, 1, 1);    // Unset RO
+               }
+       }
+
+       if( fail ) {
+               DEBUGS("ElfRelocate: Failure");
+               return NULL;
+       }       
+
+       #undef _doRelocate
+
        DEBUGS("ElfRelocate: RETURN 0x%x to %p", hdr->entrypoint + iBaseDiff, __builtin_return_address(0));
        return (void*)(intptr_t)( hdr->entrypoint + iBaseDiff );
 }
@@ -523,12 +571,53 @@ int Elf32GetSymbol(void *Base, const char *Name, void **ret, size_t *Size)
 }
 
 #ifdef SUPPORT_ELF64
+typedef int (*t_elf64_doreloc)(void *Base, const char *strtab, Elf64_Sym *symtab, Elf64_Xword r_info, void *ptr, Elf64_Sxword addend);
+
+int _Elf64DoReloc_X86_64(void *Base, const char *strtab, Elf64_Sym *symtab, 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:
+               if( !GetSymbol(symname, &symval, NULL)  )       return 1;
+               *(uint64_t*)ptr = (uintptr_t)symval + addend;
+               break;
+       case R_X86_64_COPY: {
+               size_t  size;
+               if( !GetSymbol(symname, &symval, &size)  )      return 1;
+               memcpy(ptr, symval, size);
+               } break;
+       case R_X86_64_GLOB_DAT:
+               if( !GetSymbol(symname, &symval, NULL)  )       return 1;
+               *(uint64_t*)ptr = (uintptr_t)symval;
+               break;
+       case R_X86_64_JUMP_SLOT:
+               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);
+               return 2;
+       }
+       //DEBUGS("_Elf64DoReloc: - Good");
+       return 0;
+}
+
 void *Elf64Relocate(void *Base, char **envp, const char *Filename)
 {
         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;
@@ -554,7 +643,7 @@ 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 = 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 +752,17 @@ void *Elf64Relocate(void *Base, char **envp, const char *Filename)
        }
 
        // 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;
-               }
-       }
+       t_elf64_doreloc fpElf64DoReloc = &_Elf64DoReloc_X86_64;
+       #define _Elf64DoReloc(info, ptr, addend)        fpElf64DoReloc(Base, strtab, symtab, info, ptr, addend)
 
+       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 +772,7 @@ 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 +785,7 @@ 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 +795,16 @@ 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 +837,7 @@ 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)

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