Kernel/bin/elf.c

   1 /*\r
   2 Acess v0.1\r
   3 ELF Executable Loader Code\r
   4 */\r
   5 #include <common.h>\r
   6 #include <binary.h>\r
   7 #include "bin_elf.h"\r
   8 \r
   9 #define DEBUG   1\r
  10 #define DEBUG_WARN      1\r
  11 \r
  12 #if DEBUG\r
  13 # define DEBUGS(v...)   Log(v)\r
  14 #else\r
  15 # define DEBUGS(v...)\r
  16 # undef ENTER\r
  17 # undef LOG\r
  18 # undef LEAVE\r
  19 # define ENTER(...)\r
  20 # define LOG(...)\r
  21 # define LEAVE(...)\r
  22 #endif\r
  23 \r
  24 \r
  25 // === PROTOTYPES ===\r
  26 tBinary *Elf_Load(int fp);\r
  27  int    Elf_Relocate(void *Base);\r
  28  int    Elf_GetSymbol(void *Base, char *Name, Uint *ret);\r
  29  int    Elf_Int_DoRelocate(Uint r_info, Uint32 *ptr, Uint32 addend, Elf32_Sym *symtab, Uint base);\r
  30 Uint    Elf_Int_HashString(char *str);\r
  31 \r
  32 // === GLOBALS ===\r
  33 tBinaryType     gELF_Info = {\r
  34         NULL,\r
  35         0x464C457F, 0xFFFFFFFF, // '\x7FELF'\r
  36         "ELF",\r
  37         Elf_Load, Elf_Relocate, Elf_GetSymbol\r
  38         };\r
  39 \r
  40 // === CODE ===\r
  41 tBinary *Elf_Load(int fp)\r
  42 {\r
  43         tBinary *ret;\r
  44         Elf32_Ehdr      hdr;\r
  45         Elf32_Phdr      *phtab;\r
  46          int    i, j, k;\r
  47          int    iPageCount;\r
  48          int    count;\r
  49         \r
  50         ENTER("ifp", fp);\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.ident[0] != 0x7F || hdr.ident[1] != 'E' || hdr.ident[2] != 'L' || hdr.ident[3] != 'F') {\r
  57                 Warning("Non-ELF File was passed to the ELF loader\n");\r
  58                 LEAVE('n');\r
  59                 return NULL;\r
  60         }\r
  61         \r
  62         // Check for a program header\r
  63         if(hdr.phoff == 0) {\r
  64                 #if DEBUG_WARN\r
  65                 Warning("ELF File does not contain a program header\n");\r
  66                 #endif\r
  67                 LEAVE('n');\r
  68                 return NULL;\r
  69         }\r
  70         \r
  71         // Read Program Header Table\r
  72         phtab = malloc(sizeof(Elf32_Phdr)*hdr.phentcount);\r
  73         VFS_Seek(fp, hdr.phoff, SEEK_SET);\r
  74         VFS_Read(fp, sizeof(Elf32_Phdr)*hdr.phentcount, phtab);\r
  75         \r
  76         // Count Pages\r
  77         iPageCount = 0;\r
  78         LOG("hdr.phentcount = %i", hdr.phentcount);\r
  79         for( i = 0; i < hdr.phentcount; i++ )\r
  80         {\r
  81                 // Ignore Non-LOAD types\r
  82                 if(phtab[i].Type != PT_LOAD)\r
  83                         continue;\r
  84                 iPageCount += ((phtab[i].VAddr&0xFFF) + phtab[i].MemSize + 0xFFF) >> 12;\r
  85                 LOG("phtab[%i] = {VAddr:0x%x, MemSize:0x%x}", i, phtab[i].VAddr, phtab[i].MemSize);\r
  86         }\r
  87         \r
  88         LOG("iPageCount = %i", iPageCount);\r
  89         \r
  90         // Allocate Information Structure\r
  91         ret = malloc( sizeof(tBinary) + 3*sizeof(Uint)*iPageCount );\r
  92         // Fill Info Struct\r
  93         ret->Entry = hdr.entrypoint;\r
  94         ret->Base = -1;         // Set Base to maximum value\r
  95         ret->NumPages = iPageCount;\r
  96         ret->Interpreter = NULL;\r
  97         \r
  98         // Load Pages\r
  99         j = 0;\r
 100         for( i = 0; i < hdr.phentcount; i++ )\r
 101         {\r
 102                  int    lastSize;\r
 103                 LOG("phtab[%i].Type = 0x%x", i, phtab[i].Type);\r
 104                 // Get Interpreter Name\r
 105                 if( phtab[i].Type == PT_INTERP )\r
 106                 {\r
 107                         char *tmp;\r
 108                         if(ret->Interpreter)    continue;\r
 109                         tmp = malloc(phtab[i].FileSize);\r
 110                         VFS_Seek(fp, phtab[i].Offset, 1);\r
 111                         VFS_Read(fp, phtab[i].FileSize, tmp);\r
 112                         ret->Interpreter = Binary_RegInterp(tmp);\r
 113                         LOG("Interpreter '%s'", tmp);\r
 114                         free(tmp);\r
 115                         continue;\r
 116                 }\r
 117                 // Ignore non-LOAD types\r
 118                 if(phtab[i].Type != PT_LOAD)    continue;\r
 119                 \r
 120                 // Find Base\r
 121                 if(phtab[i].VAddr < ret->Base)  ret->Base = phtab[i].VAddr;
 122 \r
 123                 k = 0;\r
 124                 \r
 125                 LOG("phtab[%i] = {VAddr:0x%x,Offset:0x%x,FileSize:0x%x}",\r
 126                         i, phtab[i].VAddr, phtab[i].Offset, phtab[i].FileSize);\r
 127                 \r
 128                 if( (phtab[i].FileSize & 0xFFF) < 0x1000 - (phtab[i].VAddr & 0xFFF) )\r
 129                         lastSize = phtab[i].FileSize;\r
 130                 else\r
 131                         lastSize = (phtab[i].FileSize & 0xFFF) + (phtab[i].VAddr & 0xFFF);\r
 132                 lastSize &= 0xFFF;\r
 133                 \r
 134                 LOG("lastSize = 0x%x", lastSize);\r
 135                 \r
 136                 // Get Pages\r
 137                 count = ( (phtab[i].VAddr&0xFFF) + phtab[i].FileSize + 0xFFF) >> 12;\r
 138                 for(;k<count;k++)\r
 139                 {\r
 140                         ret->Pages[j+k].Virtual = phtab[i].VAddr + (k<<12);\r
 141                         ret->Pages[j+k].Physical = phtab[i].Offset + (k<<12);   // Store the offset in the physical address\r
 142                         if(k != 0) {\r
 143                                 ret->Pages[j+k].Physical -= ret->Pages[j+k].Virtual&0xFFF;\r
 144                                 ret->Pages[j+k].Virtual &= ~0xFFF;\r
 145                         }\r
 146                         if(k == count-1)\r
 147                                 ret->Pages[j+k].Size = lastSize;        // Byte count in page\r
 148                         else if(k == 0)\r
 149                                 ret->Pages[j+k].Size = 4096 - (phtab[i].VAddr&0xFFF);\r
 150                         else\r
 151                                 ret->Pages[j+k].Size = 4096;\r
 152                         LOG("ret->Pages[%i].Size = 0x%x", j+k, ret->Pages[j+k].Size);\r
 153                         ret->Pages[j+k].Flags = 0;\r
 154                 }\r
 155                 count = (phtab[i].MemSize + 0xFFF) >> 12;\r
 156                 for(;k<count;k++)\r
 157                 {\r
 158                         ret->Pages[j+k].Virtual = phtab[i].VAddr + (k<<12);\r
 159                         ret->Pages[j+k].Physical = -1;  // -1 = Fill with zeros\r
 160                         if(k != 0)      ret->Pages[j+k].Virtual &= ~0xFFF;\r
 161                         if(k == count-1 && (phtab[i].MemSize & 0xFFF))\r
 162                                 ret->Pages[j+k].Size = phtab[i].MemSize & 0xFFF;        // Byte count in page\r
 163                         else\r
 164                                 ret->Pages[j+k].Size = 4096;\r
 165                         ret->Pages[j+k].Flags = 0;\r
 166                         LOG("%i - 0x%x => 0x%x - 0x%x", j+k,\r
 167                                 ret->Pages[j+k].Physical, ret->Pages[j+k].Virtual, ret->Pages[j+k].Size);\r
 168                 }\r
 169                 j += count;\r
 170         }\r
 171         \r
 172         #if 0\r
 173         LOG("Cleaning up overlaps");\r
 174         // Clear up Overlaps\r
 175         {\r
 176                 struct {\r
 177                         Uint    V;\r
 178                         Uint    P;\r
 179                         Uint    S;\r
 180                         Uint    F;\r
 181                 } *tmpRgns;\r
 182                 count = j;\r
 183                 tmpRgns = malloc(sizeof(*tmpRgns)*count);\r
 184                 // Copy\r
 185                 for(i=0;i<count;i++) {\r
 186                         tmpRgns[i].V = ret->Pages[i].Virtual;\r
 187                         tmpRgns[i].P = ret->Pages[i].Physical;\r
 188                         tmpRgns[i].S = ret->Pages[i].Size;\r
 189                         tmpRgns[i].F = ret->Pages[i].Flags;\r
 190                 }\r
 191                 // Compact\r
 192                 for(i=1,j=0; i < count; i++)\r
 193                 {                       \r
 194                         if(     tmpRgns[j].F == tmpRgns[i].F\r
 195                         &&      tmpRgns[j].V + tmpRgns[j].S == tmpRgns[i].V\r
 196                         &&      ((tmpRgns[j].P == -1 && tmpRgns[i].P == -1)\r
 197                         || (tmpRgns[j].P + tmpRgns[j].S == tmpRgns[i].P)) )\r
 198                         {\r
 199                                 tmpRgns[j].S += tmpRgns[i].S;\r
 200                         } else {\r
 201                                 j ++;\r
 202                                 tmpRgns[j].V = tmpRgns[i].V;\r
 203                                 tmpRgns[j].P = tmpRgns[i].P;\r
 204                                 tmpRgns[j].F = tmpRgns[i].F;\r
 205                                 tmpRgns[j].S = tmpRgns[i].S;\r
 206                         }\r
 207                 }\r
 208                 j ++;\r
 209                 // Count\r
 210                 count = j;      j = 0;\r
 211                 for(i=0;i<count;i++) {\r
 212                         //LogF(" Elf_Load: %i - 0x%x => 0x%x - 0x%x\n", i, tmpRgns[i].P, tmpRgns[i].V, tmpRgns[i].S);\r
 213                         tmpRgns[i].S += tmpRgns[i].V & 0xFFF;\r
 214                         if(tmpRgns[i].P != -1)  tmpRgns[i].P -= tmpRgns[i].V & 0xFFF;\r
 215                         tmpRgns[i].V &= ~0xFFF;\r
 216                         j += (tmpRgns[i].S + 0xFFF) >> 12;\r
 217                         //LogF(" Elf_Load: %i - 0x%x => 0x%x - 0x%x\n", i, tmpRgns[i].P, tmpRgns[i].V, tmpRgns[i].S);\r
 218                 }\r
 219                 // Reallocate\r
 220                 ret = realloc( ret, sizeof(tBinary) + 3*sizeof(Uint)*j );\r
 221                 if(!ret) {\r
 222                         Warning("BIN", "ElfLoad: Unable to reallocate return structure");\r
 223                         return NULL;\r
 224                 }\r
 225                 ret->NumPages = j;\r
 226                 // Split\r
 227                 k = 0;\r
 228                 for(i=0;i<count;i++) {\r
 229                         for( j = 0; j < (tmpRgns[i].S + 0xFFF) >> 12; j++,k++ ) {\r
 230                                 ret->Pages[k].Flags = tmpRgns[i].F;\r
 231                                 ret->Pages[k].Virtual = tmpRgns[i].V + (j<<12);\r
 232                                 if(tmpRgns[i].P != -1) {\r
 233                                         ret->Pages[k].Physical = tmpRgns[i].P + (j<<12);\r
 234                                 } else\r
 235                                         ret->Pages[k].Physical = -1;\r
 236                                 ret->Pages[k].Size = tmpRgns[i].S - (j << 12);\r
 237                                 // Clamp to page size\r
 238                                 if(ret->Pages[k].Size > 0x1000) ret->Pages[k].Size = 0x1000;\r
 239                         }\r
 240                 }\r
 241                 // Free Temp\r
 242                 free(tmpRgns);\r
 243         }\r
 244         #endif\r
 245         \r
 246         // Clean Up\r
 247         free(phtab);\r
 248         // Return\r
 249         LEAVE('p', ret);\r
 250         return ret;\r
 251 }\r
 252 \r
 253 // --- ELF RELOCATION ---\r
 254 // Taken from 'ld-acess.so'\r
 255 /**\r
 256  \fn int Elf_Relocate(void *Base)\r
 257  \brief Relocates a loaded ELF Executable\r
 258 */\r
 259 int Elf_Relocate(void *Base)\r
 260 {\r
 261         Elf32_Ehdr      *hdr = Base;\r
 262         Elf32_Phdr      *phtab;\r
 263          int    i, j;   // Counters\r
 264         char    *libPath;\r
 265         Uint    iRealBase = -1;\r
 266         Uint    iBaseDiff;\r
 267          int    iSegmentCount;\r
 268          int    iSymCount = 0;\r
 269         Elf32_Rel       *rel = NULL;\r
 270         Elf32_Rela      *rela = NULL;\r
 271         Uint32  *pltgot = NULL;\r
 272         void    *plt = NULL;\r
 273         Uint32  *ptr;\r
 274          int    relSz=0, relEntSz=8;\r
 275          int    relaSz=0, relaEntSz=8;\r
 276          int    pltSz=0, pltType=0;\r
 277         Elf32_Dyn       *dynamicTab = NULL;     // Dynamic Table Pointer\r
 278         char    *dynstrtab = NULL;      // .dynamic String Table\r
 279         Elf32_Sym       *dynsymtab = NULL;\r
 280         \r
 281         ENTER("pBase", Base);\r
 282         \r
 283         // Parse Program Header to get Dynamic Table\r
 284         phtab = Base + hdr->phoff;\r
 285         iSegmentCount = hdr->phentcount;\r
 286         for(i=0;i<iSegmentCount;i++)\r
 287         {\r
 288                 // Determine linked base address\r
 289                 if(phtab[i].Type == PT_LOAD && iRealBase > phtab[i].VAddr)\r
 290                         iRealBase = phtab[i].VAddr;\r
 291                 \r
 292                 // Find Dynamic Section\r
 293                 if(phtab[i].Type == PT_DYNAMIC) {\r
 294                         if(dynamicTab) {\r
 295                                 Warning("ELF", "Elf_Relocate - Multiple PT_DYNAMIC segments\n");\r
 296                                 continue;\r
 297                         }\r
 298                         dynamicTab = (void *) phtab[i].VAddr;\r
 299                         j = i;  // Save Dynamic Table ID\r
 300                         break;\r
 301                 }\r
 302         }\r
 303         \r
 304         // Check if a PT_DYNAMIC segement was found\r
 305         if(!dynamicTab) {\r
 306                 Warning("ELF", "Elf_Relocate: No PT_DYNAMIC segment in image, returning\n");\r
 307                 LEAVE('x', hdr->entrypoint);\r
 308                 return hdr->entrypoint;\r
 309         }\r
 310         \r
 311         // Page Align real base\r
 312         iRealBase &= ~0xFFF;\r
 313         \r
 314         // Adjust "Real" Base\r
 315         iBaseDiff = (Uint)Base - iRealBase;\r
 316         // Adjust Dynamic Table\r
 317         dynamicTab = (void *) ((Uint)dynamicTab + iBaseDiff);\r
 318         \r
 319         // === Get Symbol table and String Table ===\r
 320         for( j = 0; dynamicTab[j].d_tag != DT_NULL; j++)\r
 321         {\r
 322                 switch(dynamicTab[j].d_tag)\r
 323                 {\r
 324                 // --- Symbol Table ---\r
 325                 case DT_SYMTAB:\r
 326                         dynamicTab[j].d_val += iBaseDiff;\r
 327                         dynsymtab = (void*)(dynamicTab[j].d_val);\r
 328                         hdr->misc.SymTable = dynamicTab[j].d_val;       // Saved in unused bytes of ident\r
 329                         break;\r
 330                 \r
 331                 // --- String Table ---\r
 332                 case DT_STRTAB:\r
 333                         dynamicTab[j].d_val += iBaseDiff;\r
 334                         dynstrtab = (void*)(dynamicTab[j].d_val);\r
 335                         break;\r
 336                 \r
 337                 // --- Hash Table --\r
 338                 case DT_HASH:\r
 339                         dynamicTab[j].d_val += iBaseDiff;\r
 340                         iSymCount = ((Uint*)(dynamicTab[j].d_val))[1];\r
 341                         hdr->misc.HashTable = dynamicTab[j].d_val;      // Saved in unused bytes of ident\r
 342                         break;\r
 343                 }\r
 344         }\r
 345 \r
 346 \r
 347         // Alter Symbols to true base\r
 348         for(i=0;i<iSymCount;i++)\r
 349         {\r
 350                 dynsymtab[i].value += iBaseDiff;\r
 351                 dynsymtab[i].nameOfs += (Uint)dynstrtab;\r
 352                 //LOG("Sym '%s' = 0x%x (relocated)\n", dynsymtab[i].name, dynsymtab[i].value);\r
 353         }\r
 354         \r
 355         // === Add to loaded list (can be imported now) ===\r
 356         //Binary_AddLoaded( (Uint)Base );\r
 357 \r
 358         // === Parse Relocation Data ===\r
 359         for( j = 0; dynamicTab[j].d_tag != DT_NULL; j++)\r
 360         {\r
 361                 switch(dynamicTab[j].d_tag)\r
 362                 {\r
 363                 // --- Shared Library Name ---\r
 364                 case DT_SONAME:\r
 365                         LOG(".so Name '%s'\n", dynstrtab+dynamicTab[j].d_val);\r
 366                         break;\r
 367                 // --- Needed Library ---\r
 368                 case DT_NEEDED:\r
 369                         libPath = dynstrtab + dynamicTab[j].d_val;\r
 370                         LOG("Required Library '%s' (IGNORED in kernel mode)\n", libPath);\r
 371                         break;\r
 372                 // --- PLT/GOT ---\r
 373                 case DT_PLTGOT: pltgot = (void*)iBaseDiff+(dynamicTab[j].d_val);        break;\r
 374                 case DT_JMPREL: plt = (void*)(iBaseDiff+dynamicTab[j].d_val);   break;\r
 375                 case DT_PLTREL: pltType = dynamicTab[j].d_val;  break;\r
 376                 case DT_PLTRELSZ:       pltSz = dynamicTab[j].d_val;    break;\r
 377                 \r
 378                 // --- Relocation ---\r
 379                 case DT_REL:    rel = (void*)(iBaseDiff + dynamicTab[j].d_val); break;\r
 380                 case DT_RELSZ:  relSz = dynamicTab[j].d_val;    break;\r
 381                 case DT_RELENT: relEntSz = dynamicTab[j].d_val; break;\r
 382                 case DT_RELA:   rela = (void*)(iBaseDiff + dynamicTab[j].d_val);        break;\r
 383                 case DT_RELASZ: relaSz = dynamicTab[j].d_val;   break;\r
 384                 case DT_RELAENT:        relaEntSz = dynamicTab[j].d_val;        break;\r
 385                 }\r
 386         }\r
 387         \r
 388         // Parse Relocation Entries\r
 389         if(rel && relSz)\r
 390         {\r
 391                 j = relSz / relEntSz;\r
 392                 for( i = 0; i < j; i++ )\r
 393                 {\r
 394                         ptr = (void*)(iBaseDiff + rel[i].r_offset);\r
 395                         if( !Elf_Int_DoRelocate(rel[i].r_info, ptr, *ptr, dynsymtab, (Uint)Base) ) {\r
 396                                 LEAVE('x', 0);\r
 397                                 return 0;\r
 398                         }\r
 399                 }\r
 400         }\r
 401         // Parse Relocation Entries\r
 402         if(rela && relaSz)\r
 403         {\r
 404                 j = relaSz / relaEntSz;\r
 405                 for( i = 0; i < j; i++ )\r
 406                 {\r
 407                         ptr = (void*)(iBaseDiff + rela[i].r_offset);\r
 408                         if( !Elf_Int_DoRelocate(rel[i].r_info, ptr, rela[i].r_addend, dynsymtab, (Uint)Base) ) {\r
 409                                 LEAVE('x', 0);\r
 410                                 return 0;\r
 411                         }\r
 412                 }\r
 413         }\r
 414         \r
 415         // === Process PLT (Procedure Linkage Table) ===\r
 416         if(plt && pltSz)\r
 417         {\r
 418                 if(pltType == DT_REL)\r
 419                 {\r
 420                         Elf32_Rel       *pltRel = plt;\r
 421                         j = pltSz / sizeof(Elf32_Rel);\r
 422                         for(i = 0; i < j; i++)\r
 423                         {\r
 424                                 ptr = (void*)(iBaseDiff + pltRel[i].r_offset);\r
 425                                 if( !Elf_Int_DoRelocate(pltRel[i].r_info, ptr, *ptr, dynsymtab, (Uint)Base) ) {\r
 426                                         LEAVE('x', 0);\r
 427                                         return 0;\r
 428                                 }\r
 429                         }\r
 430                 }\r
 431                 else\r
 432                 {\r
 433                         Elf32_Rela      *pltRela = plt;\r
 434                         j = pltSz / sizeof(Elf32_Rela);\r
 435                         for(i=0;i<j;i++)\r
 436                         {\r
 437                                 ptr = (void*)((Uint)Base + pltRela[i].r_offset);\r
 438                                 if( !Elf_Int_DoRelocate(pltRela[i].r_info, ptr, pltRela[i].r_addend, dynsymtab, (Uint)Base) ) {\r
 439                                         LEAVE('x', 0);\r
 440                                         return 0;\r
 441                                 }\r
 442                         }\r
 443                 }\r
 444         }\r
 445         \r
 446         LEAVE('x', hdr->entrypoint);\r
 447         return hdr->entrypoint;\r
 448 }\r
 449 \r
 450 /**\r
 451  * \fn void Elf_Int_DoRelocate(Uint r_info, Uint32 *ptr, Uint32 addend, Elf32_Sym *symtab, Uint base)\r
 452  * \brief Performs a relocation\r
 453  * \param r_info        Field from relocation entry\r
 454  * \param ptr   Pointer to location of relocation\r
 455  * \param addend        Value to add to symbol\r
 456  * \param symtab        Symbol Table\r
 457  * \param base  Base of loaded binary\r
 458  */\r
 459 int Elf_Int_DoRelocate(Uint r_info, Uint32 *ptr, Uint32 addend, Elf32_Sym *symtab, Uint base)\r
 460 {\r
 461         Uint    val;\r
 462          int    type = ELF32_R_TYPE(r_info);\r
 463          int    sym = ELF32_R_SYM(r_info);\r
 464         char    *sSymName = symtab[sym].name;\r
 465         \r
 466         //LogF("Elf_Int_DoRelocate: (r_info=0x%x, ptr=0x%x, addend=0x%x, .., base=0x%x)\n",\r
 467         //      r_info, ptr, addend, base);\r
 468         \r
 469         switch( type )\r
 470         {\r
 471         // Standard 32 Bit Relocation (S+A)\r
 472         case R_386_32:\r
 473                 if( !Elf_GetSymbol((void*)base, sSymName, &val) )       // Search this binary first\r
 474                         if( !Binary_GetSymbol( sSymName, &val ) )\r
 475                                 return 0;\r
 476                 //LOG("R_386_32 *0x%x += 0x%x('%s')", ptr, val, sSymName);\r
 477                 *ptr = val + addend;\r
 478                 break;\r
 479                 \r
 480         // 32 Bit Relocation wrt. Offset (S+A-P)\r
 481         case R_386_PC32:\r
 482                 if( !Elf_GetSymbol( (void*)base, sSymName, &val ) )\r
 483                         if( !Binary_GetSymbol( sSymName, &val ) )\r
 484                                 return 0;\r
 485                 //LOG("R_386_PC32 *0x%x = 0x%x + 0x%x('%s') - 0x%x", ptr, *ptr, val, sSymName, (Uint)ptr );\r
 486                 // TODO: Check if it needs the true value of ptr or the compiled value\r
 487                 // NOTE: Testing using true value\r
 488                 *ptr = val + addend - (Uint)ptr;\r
 489                 break;\r
 490 \r
 491         // Absolute Value of a symbol (S)\r
 492         case R_386_GLOB_DAT:\r
 493                 if( !Elf_GetSymbol( (void*)base, sSymName, &val ) )\r
 494                         if( !Binary_GetSymbol( sSymName, &val ) )\r
 495                                 return 0;\r
 496                 //LOG("R_386_GLOB_DAT *0x%x = 0x%x (%s)", ptr, val, sSymName);\r
 497                 *ptr = val;\r
 498                 break;\r
 499         \r
 500         // Absolute Value of a symbol (S)\r
 501         case R_386_JMP_SLOT:\r
 502                 if( !Elf_GetSymbol( (void*)base, sSymName, &val ) )\r
 503                         if( !Binary_GetSymbol( sSymName, &val ) )\r
 504                                 return 0;\r
 505                 //LOG("R_386_JMP_SLOT *0x%x = 0x%x (%s)", ptr, val, sSymName);\r
 506                 *ptr = val;\r
 507                 break;\r
 508 \r
 509         // Base Address (B+A)\r
 510         case R_386_RELATIVE:\r
 511                 //LOG("R_386_RELATIVE *0x%x = 0x%x + 0x%x", ptr, base, addend);\r
 512                 *ptr = base + addend;\r
 513                 break;\r
 514                 \r
 515         default:\r
 516                 LOG("Rel 0x%x: 0x%x,%i", ptr, sym, type);\r
 517                 break;\r
 518         }\r
 519         return 1;\r
 520 }\r
 521 \r
 522 /**\r
 523  * \fn int Elf_GetSymbol(void *Base, char *name, Uint *ret)\r
 524  * \brief Get a symbol from the loaded binary\r
 525  */\r
 526 int Elf_GetSymbol(void *Base, char *Name, Uint *ret)\r
 527 {\r
 528         Elf32_Ehdr      *hdr = (void*)Base;\r
 529         Elf32_Sym       *symtab;\r
 530          int    nbuckets = 0;\r
 531          int    iSymCount = 0;\r
 532          int    i;\r
 533         Uint    *pBuckets;\r
 534         Uint    *pChains;\r
 535         Uint    iNameHash;\r
 536 \r
 537         if(!Base)       return 0;\r
 538 \r
 539         pBuckets = (void *) hdr->misc.HashTable;\r
 540         symtab = (void *) hdr->misc.SymTable;\r
 541         \r
 542         nbuckets = pBuckets[0];\r
 543         iSymCount = pBuckets[1];\r
 544         pBuckets = &pBuckets[2];\r
 545         pChains = &pBuckets[ nbuckets ];\r
 546         \r
 547         // Get hash\r
 548         iNameHash = Elf_Int_HashString(Name);\r
 549         iNameHash %= nbuckets;\r
 550 \r
 551         // Check Bucket\r
 552         i = pBuckets[ iNameHash ];\r
 553         if(symtab[i].shndx != SHN_UNDEF && strcmp(symtab[i].name, Name) == 0) {\r
 554                 *ret = symtab[ i ].value;\r
 555                 return 1;\r
 556         }\r
 557         \r
 558         // Walk Chain\r
 559         while(pChains[i] != STN_UNDEF)\r
 560         {\r
 561                 i = pChains[i];\r
 562                 if(symtab[i].shndx != SHN_UNDEF && strcmp(symtab[ i ].name, Name) == 0) {\r
 563                         *ret = symtab[ i ].value;\r
 564                         return 1;\r
 565                 }\r
 566         }\r
 567         return 0;\r
 568 }\r
 569 \r
 570 /**\r
 571  * \fn Uint Elf_Int_HashString(char *str)\r
 572  * \brief Hash a string in the ELF format\r
 573  * \param str   String to hash\r
 574  * \return Hash value\r
 575  */\r
 576 Uint Elf_Int_HashString(char *str)\r
 577 {\r
 578         Uint    h = 0, g;\r
 579         while(*str)\r
 580         {\r
 581                 h = (h << 4) + *str++;\r
 582                 if( (g = h & 0xf0000000) )\r
 583                         h ^= g >> 24;\r
 584                 h &= ~g;\r
 585         }\r
 586         return h;\r
 587 }\r