KernelLand/Kernel/bin/elf.c

   1 /*\r
   2  * Acess v0.1\r
   3  * ELF Executable Loader Code\r
   4  */\r
   5 #define DEBUG   0\r
   6 #include <acess.h>\r
   7 #include <binary.h>\r
   8 \r
   9 #define _COMMON_H\r
  10 #define SysDebug(v...)  LOG(v)\r
  11 #if BITS <= 32\r
  12 # define DISABLE_ELF64\r
  13 #endif\r
  14 static int      GetSymbol(const char *Name, void **Value, size_t *Size);\r
  15 static int      GetSymbol(const char *Name, void **Value, size_t *Size) {\r
  16         Uint val;\r
  17         if(Binary_GetSymbol(Name, &val))\r
  18                 return 0;\r
  19         if(Size)\r
  20                 *Size=0;\r
  21         *Value = (void*)val;\r
  22         return 1;\r
  23 }\r
  24 #define AddLoaded(a,b)  do{}while(0)\r
  25 #define LoadLibrary(a,b,c)      (Log_Debug("ELF", "Module requested lib '%s'",a),0)\r
  26 #define SysSetMemFlags(ad,f,m)  do{}while(0)\r
  27 #include "../../../Usermode/Libraries/ld-acess.so_src/elf.c"\r
  28 \r
  29 #define DEBUG_WARN      1\r
  30 \r
  31 // === PROTOTYPES ===\r
  32 tBinary *Elf_Load(int fp);\r
  33 tBinary *Elf_Load64(int fp, Elf64_Ehdr *hdr);\r
  34 tBinary *Elf_Load32(int fp, Elf32_Ehdr *hdr);\r
  35  int    Elf_Relocate(void *Base);\r
  36  int    Elf_GetSymbol(void *Base, const char *Name, Uint *Ret);\r
  37 Uint    Elf_Int_HashString(const char *str);\r
  38 \r
  39 // === GLOBALS ===\r
  40 tBinaryType     gELF_Info = {\r
  41         NULL,\r
  42         0x464C457F, 0xFFFFFFFF, // '\x7FELF'\r
  43         "ELF",\r
  44         Elf_Load, Elf_Relocate, Elf_GetSymbol\r
  45         };\r
  46 \r
  47 // === CODE ===\r
  48 tBinary *Elf_Load(int fp)\r
  49 {\r
  50         Elf64_Ehdr      hdr;\r
  51         \r
  52         // Read ELF Header\r
  53         VFS_Read(fp, sizeof(hdr), &hdr);\r
  54         \r
  55         // Check the file type\r
  56         if(hdr.e_ident[0] != 0x7F || hdr.e_ident[1] != 'E' || hdr.e_ident[2] != 'L' || hdr.e_ident[3] != 'F') {\r
  57                 Log_Warning("ELF", "Non-ELF File was passed to the ELF loader");\r
  58                 return NULL;\r
  59         }\r
  60 \r
  61         switch(hdr.e_ident[4])  // EI_CLASS\r
  62         {\r
  63         case ELFCLASS32:\r
  64                 return Elf_Load32(fp, (void*)&hdr);\r
  65         case ELFCLASS64:\r
  66                 return Elf_Load64(fp, &hdr);\r
  67         default:\r
  68                 Log_Warning("ELF", "Unknown EI_CLASS value %i", hdr.e_ident[4]);\r
  69                 return NULL;\r
  70         }\r
  71 }\r
  72 \r
  73 tBinary *Elf_Load64(int FD, Elf64_Ehdr *Header)\r
  74 {\r
  75         tBinary *ret;\r
  76         Elf64_Phdr      phtab[Header->e_phnum];\r
  77          int    nLoadSegments;\r
  78          int    i, j;\r
  79         \r
  80         // Sanity check\r
  81         if( Header->e_phoff == 0 )\r
  82         {\r
  83                 Log_Warning("ELF", "No program header, panic!");\r
  84                 return NULL;\r
  85         }\r
  86         if( Header->e_shentsize != sizeof(Elf64_Shdr) ) {\r
  87                 Log_Warning("ELF", "Header gives shentsize as %i, my type is %i",\r
  88                         Header->e_shentsize, sizeof(Elf64_Shdr) );\r
  89         }\r
  90         if( Header->e_phentsize != sizeof(Elf64_Phdr) ) {\r
  91                 Log_Warning("ELF", "Header gives phentsize as %i, my type is %i",\r
  92                         Header->e_phentsize, sizeof(Elf64_Phdr) );\r
  93         }\r
  94 \r
  95         LOG("Header = {");\r
  96         LOG("  e_ident = %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x",\r
  97                 Header->e_ident[0], Header->e_ident[1], Header->e_ident[2], Header->e_ident[3],\r
  98                 Header->e_ident[4], Header->e_ident[5], Header->e_ident[6], Header->e_ident[7],\r
  99                 Header->e_ident[8], Header->e_ident[9], Header->e_ident[10], Header->e_ident[11],\r
 100                 Header->e_ident[12], Header->e_ident[13], Header->e_ident[14], Header->e_ident[15]\r
 101                 );\r
 102         LOG("  e_type = %i", Header->e_type);\r
 103         LOG("  e_machine = %i", Header->e_machine);\r
 104         LOG("  e_version = %i", Header->e_version);\r
 105         LOG("  e_entry   = 0x%llx", Header->e_entry);\r
 106         LOG("  e_phoff   = 0x%llx", Header->e_phoff);\r
 107         LOG("  e_shoff   = 0x%llx", Header->e_shoff);\r
 108         LOG("  e_flags   = 0x%x", Header->e_flags);\r
 109         LOG("  e_ehsize  = %i", Header->e_ehsize);\r
 110         LOG("  e_phentsize = %i", Header->e_phentsize);\r
 111         LOG("  e_phnum   = %i", Header->e_phnum);\r
 112         LOG("  e_shentsize = %i", Header->e_shentsize);\r
 113         LOG("  e_shnum   = %i", Header->e_shnum);\r
 114         LOG("  e_shstrndx = %i", Header->e_shstrndx);\r
 115         LOG("}");\r
 116 \r
 117         // Load Program Header table\r
 118         VFS_Seek(FD, Header->e_phoff, SEEK_SET);\r
 119         VFS_Read(FD, sizeof(Elf64_Phdr)*Header->e_phnum, phtab);\r
 120 \r
 121         // Count load segments\r
 122         nLoadSegments = 0;\r
 123         for( i = 0; i < Header->e_phnum; i ++ )\r
 124         {\r
 125                 if( phtab[i].p_type != PT_LOAD )        continue ;\r
 126                 nLoadSegments ++;\r
 127         }\r
 128         \r
 129         // Allocate Information Structure\r
 130         ret = malloc( sizeof(tBinary) + sizeof(tBinarySection)*nLoadSegments );\r
 131         // Fill Info Struct\r
 132         ret->Entry = Header->e_entry;\r
 133         ret->Base = -1;         // Set Base to maximum value\r
 134         ret->NumSections = nLoadSegments;\r
 135         ret->Interpreter = NULL;\r
 136 \r
 137         j = 0;  // LoadSections[] index\r
 138         for( i = 0; i < Header->e_phnum; i ++ )\r
 139         {\r
 140                 LOG("phtab[%i] = {", i);\r
 141                 LOG("  .p_type   = %i", phtab[i].p_type);\r
 142                 LOG("  .p_flags  = 0x%x", phtab[i].p_flags);\r
 143                 LOG("  .p_offset = 0x%llx", phtab[i].p_offset);\r
 144                 LOG("  .p_vaddr  = 0x%llx", phtab[i].p_vaddr);\r
 145                 LOG("  .p_paddr  = 0x%llx", phtab[i].p_paddr);\r
 146                 LOG("  .p_filesz = 0x%llx", phtab[i].p_filesz);\r
 147                 LOG("  .p_memsz  = 0x%llx", phtab[i].p_memsz);\r
 148                 LOG("  .p_align  = 0x%llx", phtab[i].p_align);\r
 149                 LOG("}");\r
 150 \r
 151                 // Get Interpreter Name\r
 152                 if( phtab[i].p_type == PT_INTERP )\r
 153                 {\r
 154                         char *tmp;\r
 155                         if(ret->Interpreter)    continue;\r
 156                         tmp = malloc(phtab[i].p_filesz);\r
 157                         VFS_Seek(FD, phtab[i].p_offset, 1);\r
 158                         VFS_Read(FD, phtab[i].p_filesz, tmp);\r
 159                         ret->Interpreter = Binary_RegInterp(tmp);\r
 160                         LOG("Interpreter '%s'", tmp);\r
 161                         free(tmp);\r
 162                         continue;\r
 163                 }\r
 164                 \r
 165                 if( phtab[i].p_type != PT_LOAD )        continue ;\r
 166                 \r
 167                 // Find the executable base\r
 168                 if( phtab[i].p_vaddr < ret->Base )      ret->Base = phtab[i].p_vaddr;\r
 169 \r
 170                 ret->LoadSections[j].Offset = phtab[i].p_offset;\r
 171                 ret->LoadSections[j].Virtual = phtab[i].p_vaddr;\r
 172                 ret->LoadSections[j].FileSize = phtab[i].p_filesz;\r
 173                 ret->LoadSections[j].MemSize = phtab[i].p_memsz;\r
 174                 \r
 175                 ret->LoadSections[j].Flags = 0;\r
 176                 if( !(phtab[i].p_flags & PF_W) )\r
 177                         ret->LoadSections[j].Flags |= BIN_SECTFLAG_RO;\r
 178                 if( phtab[i].p_flags & PF_X )\r
 179                         ret->LoadSections[j].Flags |= BIN_SECTFLAG_EXEC;\r
 180                 j ++;\r
 181         }\r
 182 \r
 183         return ret;\r
 184 }\r
 185 \r
 186 tBinary *Elf_Load32(int FD, Elf32_Ehdr *Header)\r
 187 {\r
 188         tBinary *ret;\r
 189         Elf32_Phdr      *phtab;\r
 190          int    i, j;\r
 191          int    iLoadCount;\r
 192 \r
 193         ENTER("xFD", FD);\r
 194 \r
 195         // Check architecture with current CPU\r
 196         // - TODO: Support kernel level emulation\r
 197         #if ARCH_IS_x86\r
 198         if( Header->machine != EM_386 )\r
 199         {\r
 200                 Log_Warning("ELF", "Unknown architecure on ELF-32");\r
 201                 LEAVE_RET('n');\r
 202                 return NULL;\r
 203         }\r
 204         #endif\r
 205 \r
 206         // Check for a program header\r
 207         if(Header->phoff == 0) {\r
 208                 #if DEBUG_WARN\r
 209                 Log_Warning("ELF", "File does not contain a program header (phoff == 0)");\r
 210                 #endif\r
 211                 LEAVE('n');\r
 212                 return NULL;\r
 213         }\r
 214         \r
 215         // Read Program Header Table\r
 216         phtab = malloc( sizeof(Elf32_Phdr) * Header->phentcount );\r
 217         if( !phtab ) {\r
 218                 LEAVE('n');\r
 219                 return NULL;\r
 220         }\r
 221         LOG("hdr.phoff = 0x%08x", Header->phoff);\r
 222         VFS_Seek(FD, Header->phoff, SEEK_SET);\r
 223         VFS_Read(FD, sizeof(Elf32_Phdr)*Header->phentcount, phtab);\r
 224         \r
 225         // Count Pages\r
 226         iLoadCount = 0;\r
 227         LOG("Header->phentcount = %i", Header->phentcount);\r
 228         for( i = 0; i < Header->phentcount; i++ )\r
 229         {\r
 230                 // Ignore Non-LOAD types\r
 231                 if(phtab[i].Type != PT_LOAD)\r
 232                         continue;\r
 233                 iLoadCount ++;\r
 234                 LOG("phtab[%i] = {VAddr:0x%x, MemSize:0x%x}", i, phtab[i].VAddr, phtab[i].MemSize);\r
 235         }\r
 236         \r
 237         LOG("iLoadCount = %i", iLoadCount);\r
 238         \r
 239         // Allocate Information Structure\r
 240         ret = malloc( sizeof(tBinary) + sizeof(tBinarySection)*iLoadCount );\r
 241         // Fill Info Struct\r
 242         ret->Entry = Header->entrypoint;\r
 243         ret->Base = -1;         // Set Base to maximum value\r
 244         ret->NumSections = iLoadCount;\r
 245         ret->Interpreter = NULL;\r
 246         \r
 247         // Load Pages\r
 248         j = 0;\r
 249         for( i = 0; i < Header->phentcount; i++ )\r
 250         {\r
 251                 //LOG("phtab[%i].Type = 0x%x", i, phtab[i].Type);\r
 252                 LOG("phtab[%i] = {", i);\r
 253                 LOG(" .Type = 0x%08x", phtab[i].Type);\r
 254                 LOG(" .Offset = 0x%08x", phtab[i].Offset);\r
 255                 LOG(" .VAddr = 0x%08x", phtab[i].VAddr);\r
 256                 LOG(" .PAddr = 0x%08x", phtab[i].PAddr);\r
 257                 LOG(" .FileSize = 0x%08x", phtab[i].FileSize);\r
 258                 LOG(" .MemSize = 0x%08x", phtab[i].MemSize);\r
 259                 LOG(" .Flags = 0x%08x", phtab[i].Flags);\r
 260                 LOG(" .Align = 0x%08x", phtab[i].Align);\r
 261                 LOG(" }");\r
 262                 // Get Interpreter Name\r
 263                 if( phtab[i].Type == PT_INTERP )\r
 264                 {\r
 265                         char *tmp;\r
 266                         if(ret->Interpreter)    continue;\r
 267                         tmp = malloc(phtab[i].FileSize);\r
 268                         VFS_Seek(FD, phtab[i].Offset, 1);\r
 269                         VFS_Read(FD, phtab[i].FileSize, tmp);\r
 270                         ret->Interpreter = Binary_RegInterp(tmp);\r
 271                         LOG("Interpreter '%s'", tmp);\r
 272                         free(tmp);\r
 273                         continue;\r
 274                 }\r
 275                 // Ignore non-LOAD types\r
 276                 if(phtab[i].Type != PT_LOAD)    continue;\r
 277                 \r
 278                 // Find Base\r
 279                 if(phtab[i].VAddr < ret->Base)  ret->Base = phtab[i].VAddr;\r
 280                 \r
 281                 LOG("phtab[%i] = {VAddr:0x%x,Offset:0x%x,FileSize:0x%x}",\r
 282                         i, phtab[i].VAddr, phtab[i].Offset, phtab[i].FileSize);\r
 283                 \r
 284                 ret->LoadSections[j].Offset = phtab[i].Offset;\r
 285                 ret->LoadSections[j].FileSize = phtab[i].FileSize;\r
 286                 ret->LoadSections[j].Virtual = phtab[i].VAddr;\r
 287                 ret->LoadSections[j].MemSize = phtab[i].MemSize;\r
 288                 ret->LoadSections[j].Flags = 0;\r
 289                 if( !(phtab[i].Flags & PF_W) )\r
 290                         ret->LoadSections[j].Flags |= BIN_SECTFLAG_RO;\r
 291                 if( phtab[i].Flags & PF_X )\r
 292                         ret->LoadSections[j].Flags |= BIN_SECTFLAG_EXEC;\r
 293                 j ++;\r
 294         }\r
 295         \r
 296         // Clean Up\r
 297         free(phtab);\r
 298         // Return\r
 299         LEAVE('p', ret);\r
 300         return ret;\r
 301 }\r
 302 \r
 303 int Elf_Relocate(void *Base)\r
 304 {\r
 305         return ElfRelocate(Base, (char**){NULL}, "") != NULL;\r
 306 }\r
 307 int Elf_GetSymbol(void *Base, const char *Name, Uint *ret)\r
 308 {\r
 309         return ElfGetSymbol(Base, Name, (void**)ret, NULL);\r
 310 }\r
 311 \r