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 #include "elf.h"\r
   9 \r
  10 #define DEBUG_WARN      1\r
  11 \r
  12 // === PROTOTYPES ===\r
  13 tBinary *Elf_Load(int fp);\r
  14  int    Elf_Relocate(void *Base);\r
  15  int    Elf_GetSymbol(void *Base, const char *Name, Uint *ret);\r
  16  int    Elf_Int_DoRelocate(Uint r_info, Uint32 *ptr, Uint32 addend, Elf32_Sym *symtab, Uint base);\r
  17 Uint    Elf_Int_HashString(const char *str);\r
  18 \r
  19 // === GLOBALS ===\r
  20 tBinaryType     gELF_Info = {\r
  21         NULL,\r
  22         0x464C457F, 0xFFFFFFFF, // '\x7FELF'\r
  23         "ELF",\r
  24         Elf_Load, Elf_Relocate, Elf_GetSymbol\r
  25         };\r
  26 \r
  27 // === CODE ===\r
  28 tBinary *Elf_Load(int fp)\r
  29 {\r
  30         tBinary *ret;\r
  31         Elf32_Ehdr      hdr;\r
  32         Elf32_Phdr      *phtab;\r
  33          int    i, j, k;\r
  34          int    iPageCount;\r
  35          int    count;\r
  36         \r
  37         ENTER("xfp", fp);\r
  38         \r
  39         // Read ELF Header\r
  40         VFS_Read(fp, sizeof(hdr), &hdr);\r
  41         \r
  42         // Check the file type\r
  43         if(hdr.ident[0] != 0x7F || hdr.ident[1] != 'E' || hdr.ident[2] != 'L' || hdr.ident[3] != 'F') {\r
  44                 Log_Warning("ELF", "Non-ELF File was passed to the ELF loader");\r
  45                 LEAVE('n');\r
  46                 return NULL;\r
  47         }\r
  48         \r
  49         // Check for a program header\r
  50         if(hdr.phoff == 0) {\r
  51                 #if DEBUG_WARN\r
  52                 Log_Warning("ELF", "File does not contain a program header (phoff == 0)");\r
  53                 #endif\r
  54                 LEAVE('n');\r
  55                 return NULL;\r
  56         }\r
  57         \r
  58         // Read Program Header Table\r
  59         phtab = malloc( sizeof(Elf32_Phdr) * hdr.phentcount );\r
  60         if( !phtab ) {\r
  61                 LEAVE('n');\r
  62                 return NULL;\r
  63         }\r
  64         LOG("hdr.phoff = 0x%08x", hdr.phoff);\r
  65         VFS_Seek(fp, hdr.phoff, SEEK_SET);\r
  66         VFS_Read(fp, sizeof(Elf32_Phdr)*hdr.phentcount, phtab);\r
  67         \r
  68         // Count Pages\r
  69         iPageCount = 0;\r
  70         LOG("hdr.phentcount = %i", hdr.phentcount);\r
  71         for( i = 0; i < hdr.phentcount; i++ )\r
  72         {\r
  73                 // Ignore Non-LOAD types\r
  74                 if(phtab[i].Type != PT_LOAD)\r
  75                         continue;\r
  76                 iPageCount += ((phtab[i].VAddr&0xFFF) + phtab[i].MemSize + 0xFFF) >> 12;\r
  77                 LOG("phtab[%i] = {VAddr:0x%x, MemSize:0x%x}", i, phtab[i].VAddr, phtab[i].MemSize);\r
  78         }\r
  79         \r
  80         LOG("iPageCount = %i", iPageCount);\r
  81         \r
  82         // Allocate Information Structure\r
  83         ret = malloc( sizeof(tBinary) + sizeof(tBinaryPage)*iPageCount );\r
  84         // Fill Info Struct\r
  85         ret->Entry = hdr.entrypoint;\r
  86         ret->Base = -1;         // Set Base to maximum value\r
  87         ret->NumPages = iPageCount;\r
  88         ret->Interpreter = NULL;\r
  89         \r
  90         // Load Pages\r
  91         j = 0;\r
  92         for( i = 0; i < hdr.phentcount; i++ )\r
  93         {\r
  94                  int    lastSize;\r
  95                 //LOG("phtab[%i].Type = 0x%x", i, phtab[i].Type);\r
  96                 LOG("phtab[%i] = {", i);\r
  97                 LOG(" .Type = 0x%08x", phtab[i].Type);\r
  98                 LOG(" .Offset = 0x%08x", phtab[i].Offset);\r
  99                 LOG(" .VAddr = 0x%08x", phtab[i].VAddr);\r
 100                 LOG(" .PAddr = 0x%08x", phtab[i].PAddr);\r
 101                 LOG(" .FileSize = 0x%08x", phtab[i].FileSize);\r
 102                 LOG(" .MemSize = 0x%08x", phtab[i].MemSize);\r
 103                 LOG(" .Flags = 0x%08x", phtab[i].Flags);\r
 104                 LOG(" .Align = 0x%08x", phtab[i].Align);\r
 105                 LOG(" }");\r
 106                 // Get Interpreter Name\r
 107                 if( phtab[i].Type == PT_INTERP )\r
 108                 {\r
 109                         char *tmp;\r
 110                         if(ret->Interpreter)    continue;\r
 111                         tmp = malloc(phtab[i].FileSize);\r
 112                         VFS_Seek(fp, phtab[i].Offset, 1);\r
 113                         VFS_Read(fp, phtab[i].FileSize, tmp);\r
 114                         ret->Interpreter = Binary_RegInterp(tmp);\r
 115                         LOG("Interpreter '%s'", tmp);\r
 116                         free(tmp);\r
 117                         continue;\r
 118                 }\r
 119                 // Ignore non-LOAD types\r
 120                 if(phtab[i].Type != PT_LOAD)    continue;\r
 121                 \r
 122                 // Find Base\r
 123                 if(phtab[i].VAddr < ret->Base)  ret->Base = phtab[i].VAddr;\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                 lastSize = phtab[i].FileSize;\r
 137                 \r
 138                 // Get Pages\r
 139                 count = ( (phtab[i].VAddr&0xFFF) + phtab[i].FileSize + 0xFFF) >> 12;\r
 140                 for( k = 0; k < count; k ++ )\r
 141                 {\r
 142                         ret->Pages[j+k].Virtual = phtab[i].VAddr + (k<<12);\r
 143                         ret->Pages[j+k].Physical = phtab[i].Offset + (k<<12);   // Store the offset in the physical address\r
 144                         if(k != 0) {\r
 145                                 ret->Pages[j+k].Physical -= ret->Pages[j+k].Virtual&0xFFF;\r
 146                                 ret->Pages[j+k].Virtual &= ~0xFFF;\r
 147                         }\r
 148                         if(k == count-1)\r
 149                                 ret->Pages[j+k].Size = lastSize;        // Byte count in page\r
 150                         else if(k == 0)\r
 151                                 ret->Pages[j+k].Size = 4096 - (phtab[i].VAddr&0xFFF);\r
 152                         else\r
 153                                 ret->Pages[j+k].Size = 4096;\r
 154                         LOG("ret->Pages[%i].Size = 0x%x", j+k, ret->Pages[j+k].Size);\r
 155                         ret->Pages[j+k].Flags = 0;\r
 156                         lastSize -= ret->Pages[j+k].Size;\r
 157                 }\r
 158                 count = (phtab[i].MemSize + 0xFFF) >> 12;\r
 159                 for(;k<count;k++)\r
 160                 {\r
 161                         ret->Pages[j+k].Virtual = phtab[i].VAddr + (k<<12);\r
 162                         ret->Pages[j+k].Physical = -1;  // -1 = Fill with zeros\r
 163                         if(k != 0)      ret->Pages[j+k].Virtual &= ~0xFFF;\r
 164                         if(k == count-1 && (phtab[i].MemSize & 0xFFF))\r
 165                                 ret->Pages[j+k].Size = phtab[i].MemSize & 0xFFF;        // Byte count in page\r
 166                         else\r
 167                                 ret->Pages[j+k].Size = 4096;\r
 168                         ret->Pages[j+k].Flags = 0;\r
 169                         LOG("%i - 0x%x => 0x%x - 0x%x", j+k,\r
 170                                 ret->Pages[j+k].Physical, ret->Pages[j+k].Virtual, ret->Pages[j+k].Size);\r
 171                 }\r
 172                 j += count;\r
 173         }\r
 174         \r
 175         #if 0\r
 176         LOG("Cleaning up overlaps");\r
 177         // Clear up Overlaps\r
 178         {\r
 179                 struct {\r
 180                         Uint    V;\r
 181                         Uint    P;\r
 182                         Uint    S;\r
 183                         Uint    F;\r
 184                 } *tmpRgns;\r
 185                 count = j;\r
 186                 tmpRgns = malloc(sizeof(*tmpRgns)*count);\r
 187                 // Copy\r
 188                 for(i=0;i<count;i++) {\r
 189                         tmpRgns[i].V = ret->Pages[i].Virtual;\r
 190                         tmpRgns[i].P = ret->Pages[i].Physical;\r
 191                         tmpRgns[i].S = ret->Pages[i].Size;\r
 192                         tmpRgns[i].F = ret->Pages[i].Flags;\r
 193                 }\r
 194                 // Compact\r
 195                 for(i=1,j=0; i < count; i++)\r
 196                 {                       \r
 197                         if(     tmpRgns[j].F == tmpRgns[i].F\r
 198                         &&      tmpRgns[j].V + tmpRgns[j].S == tmpRgns[i].V\r
 199                         &&      ((tmpRgns[j].P == -1 && tmpRgns[i].P == -1)\r
 200                         || (tmpRgns[j].P + tmpRgns[j].S == tmpRgns[i].P)) )\r
 201                         {\r
 202                                 tmpRgns[j].S += tmpRgns[i].S;\r
 203                         } else {\r
 204                                 j ++;\r
 205                                 tmpRgns[j].V = tmpRgns[i].V;\r
 206                                 tmpRgns[j].P = tmpRgns[i].P;\r
 207                                 tmpRgns[j].F = tmpRgns[i].F;\r
 208                                 tmpRgns[j].S = tmpRgns[i].S;\r
 209                         }\r
 210                 }\r
 211                 j ++;\r
 212                 // Count\r
 213                 count = j;      j = 0;\r
 214                 for(i=0;i<count;i++) {\r
 215                         //LogF(" Elf_Load: %i - 0x%x => 0x%x - 0x%x\n", i, tmpRgns[i].P, tmpRgns[i].V, tmpRgns[i].S);\r
 216                         tmpRgns[i].S += tmpRgns[i].V & 0xFFF;\r
 217                         if(tmpRgns[i].P != -1)  tmpRgns[i].P -= tmpRgns[i].V & 0xFFF;\r
 218                         tmpRgns[i].V &= ~0xFFF;\r
 219                         j += (tmpRgns[i].S + 0xFFF) >> 12;\r
 220                         //LogF(" Elf_Load: %i - 0x%x => 0x%x - 0x%x\n", i, tmpRgns[i].P, tmpRgns[i].V, tmpRgns[i].S);\r
 221                 }\r
 222                 // Reallocate\r
 223                 ret = realloc( ret, sizeof(tBinary) + 3*sizeof(Uint)*j );\r
 224                 if(!ret) {\r
 225                         Log_Warning("BIN", "ElfLoad: Unable to reallocate return structure");\r
 226                         return NULL;\r
 227                 }\r
 228                 ret->NumPages = j;\r
 229                 // Split\r
 230                 k = 0;\r
 231                 for(i=0;i<count;i++) {\r
 232                         for( j = 0; j < (tmpRgns[i].S + 0xFFF) >> 12; j++,k++ ) {\r
 233                                 ret->Pages[k].Flags = tmpRgns[i].F;\r
 234                                 ret->Pages[k].Virtual = tmpRgns[i].V + (j<<12);\r
 235                                 if(tmpRgns[i].P != -1) {\r
 236                                         ret->Pages[k].Physical = tmpRgns[i].P + (j<<12);\r
 237                                 } else\r
 238                                         ret->Pages[k].Physical = -1;\r
 239                                 ret->Pages[k].Size = tmpRgns[i].S - (j << 12);\r
 240                                 // Clamp to page size\r
 241                                 if(ret->Pages[k].Size > 0x1000) ret->Pages[k].Size = 0x1000;\r
 242                         }\r
 243                 }\r
 244                 // Free Temp\r
 245                 free(tmpRgns);\r
 246         }\r
 247         #endif\r
 248         \r
 249         // Clean Up\r
 250         free(phtab);\r
 251         // Return\r
 252         LEAVE('p', ret);\r
 253         return ret;\r
 254 }\r
 255 \r
 256 // --- ELF RELOCATION ---\r
 257 // Taken from 'ld-acess.so'\r
 258 /**\r
 259  \fn int Elf_Relocate(void *Base)\r
 260  \brief Relocates a loaded ELF Executable\r
 261 */\r
 262 int Elf_Relocate(void *Base)\r
 263 {\r
 264         Elf32_Ehdr      *hdr = Base;\r
 265         Elf32_Phdr      *phtab;\r
 266          int    i, j;   // Counters\r
 267         char    *libPath;\r
 268         Uint    iRealBase = -1;\r
 269         Uint    iBaseDiff;\r
 270          int    iSegmentCount;\r
 271          int    iSymCount = 0;\r
 272         Elf32_Rel       *rel = NULL;\r
 273         Elf32_Rela      *rela = NULL;\r
 274         Uint32  *pltgot = NULL;\r
 275         void    *plt = NULL;\r
 276         Uint32  *ptr;\r
 277          int    relSz=0, relEntSz=8;\r
 278          int    relaSz=0, relaEntSz=8;\r
 279          int    pltSz=0, pltType=0;\r
 280         Elf32_Dyn       *dynamicTab = NULL;     // Dynamic Table Pointer\r
 281         char    *dynstrtab = NULL;      // .dynamic String Table\r
 282         Elf32_Sym       *dynsymtab = NULL;\r
 283          int    bFailed = 0;\r
 284         \r
 285         ENTER("pBase", Base);\r
 286         \r
 287         // Parse Program Header to get Dynamic Table\r
 288         phtab = (void *)( (tVAddr)Base + hdr->phoff );\r
 289         iSegmentCount = hdr->phentcount;\r
 290         for(i = 0; i < iSegmentCount; i ++ )\r
 291         {\r
 292                 // Determine linked base address\r
 293                 if(phtab[i].Type == PT_LOAD && iRealBase > phtab[i].VAddr)\r
 294                         iRealBase = phtab[i].VAddr;\r
 295                 \r
 296                 // Find Dynamic Section\r
 297                 if(phtab[i].Type == PT_DYNAMIC) {\r
 298                         if(dynamicTab) {\r
 299                                 Log_Warning("ELF", "Elf_Relocate - Multiple PT_DYNAMIC segments\n");\r
 300                                 continue;\r
 301                         }\r
 302                         dynamicTab = (void *) (tVAddr) phtab[i].VAddr;\r
 303                         j = i;  // Save Dynamic Table ID\r
 304                         break;\r
 305                 }\r
 306         }\r
 307         \r
 308         // Check if a PT_DYNAMIC segement was found\r
 309         if(!dynamicTab) {\r
 310                 Log_Warning("ELF", "Elf_Relocate: No PT_DYNAMIC segment in image, returning\n");\r
 311                 LEAVE('x', hdr->entrypoint);\r
 312                 return hdr->entrypoint;\r
 313         }\r
 314         \r
 315         // Page Align real base\r
 316         iRealBase &= ~0xFFF;\r
 317         \r
 318         // Adjust "Real" Base\r
 319         iBaseDiff = (Uint)Base - iRealBase;\r
 320         // Adjust Dynamic Table\r
 321         dynamicTab = (void *) ((Uint)dynamicTab + iBaseDiff);\r
 322         \r
 323         // === Get Symbol table and String Table ===\r
 324         for( j = 0; dynamicTab[j].d_tag != DT_NULL; j++)\r
 325         {\r
 326                 switch(dynamicTab[j].d_tag)\r
 327                 {\r
 328                 // --- Symbol Table ---\r
 329                 case DT_SYMTAB:\r
 330                         dynamicTab[j].d_val += iBaseDiff;\r
 331                         dynsymtab = (void*) (tVAddr) dynamicTab[j].d_val;\r
 332                         hdr->misc.SymTable = dynamicTab[j].d_val;       // Saved in unused bytes of ident\r
 333                         break;\r
 334                 \r
 335                 // --- String Table ---\r
 336                 case DT_STRTAB:\r
 337                         dynamicTab[j].d_val += iBaseDiff;\r
 338                         dynstrtab = (void*) (tVAddr) dynamicTab[j].d_val;\r
 339                         break;\r
 340                 \r
 341                 // --- Hash Table --\r
 342                 case DT_HASH:\r
 343                         dynamicTab[j].d_val += iBaseDiff;\r
 344                         iSymCount = ((Uint*)((tVAddr)dynamicTab[j].d_val))[1];\r
 345                         hdr->misc.HashTable = dynamicTab[j].d_val;      // Saved in unused bytes of ident\r
 346                         break;\r
 347                 }\r
 348         }\r
 349 \r
 350         if( !dynsymtab && iSymCount > 0 ) {\r
 351                 Log_Warning("ELF", "Elf_Relocate: No Dynamic symbol table, but count >0");\r
 352                 return 0;\r
 353         }\r
 354 \r
 355         // Alter Symbols to true base\r
 356         for(i = 0; i < iSymCount; i ++)\r
 357         {\r
 358                 dynsymtab[i].value += iBaseDiff;\r
 359                 dynsymtab[i].nameOfs += (Uint)dynstrtab;\r
 360                 //LOG("Sym '%s' = 0x%x (relocated)\n", dynsymtab[i].name, dynsymtab[i].value);\r
 361         }\r
 362         \r
 363         // === Add to loaded list (can be imported now) ===\r
 364         //Binary_AddLoaded( (Uint)Base );\r
 365 \r
 366         // === Parse Relocation Data ===\r
 367         for( j = 0; dynamicTab[j].d_tag != DT_NULL; j++)\r
 368         {\r
 369                 switch(dynamicTab[j].d_tag)\r
 370                 {\r
 371                 // --- Shared Library Name ---\r
 372                 case DT_SONAME:\r
 373                         LOG(".so Name '%s'\n", dynstrtab+dynamicTab[j].d_val);\r
 374                         break;\r
 375                 // --- Needed Library ---\r
 376                 case DT_NEEDED:\r
 377                         libPath = dynstrtab + dynamicTab[j].d_val;\r
 378                         Log_Notice("ELF", "%p - Required Library '%s' (Ignored in kernel mode)\n", Base, libPath);\r
 379                         break;\r
 380                 // --- PLT/GOT ---\r
 381                 case DT_PLTGOT: pltgot = (void*)(iBaseDiff+dynamicTab[j].d_val);        break;\r
 382                 case DT_JMPREL: plt = (void*)(iBaseDiff+dynamicTab[j].d_val);   break;\r
 383                 case DT_PLTREL: pltType = dynamicTab[j].d_val;  break;\r
 384                 case DT_PLTRELSZ:       pltSz = dynamicTab[j].d_val;    break;\r
 385                 \r
 386                 // --- Relocation ---\r
 387                 case DT_REL:    rel = (void*)(iBaseDiff + dynamicTab[j].d_val); break;\r
 388                 case DT_RELSZ:  relSz = dynamicTab[j].d_val;    break;\r
 389                 case DT_RELENT: relEntSz = dynamicTab[j].d_val; break;\r
 390                 \r
 391                 case DT_RELA:   rela = (void*)(iBaseDiff + dynamicTab[j].d_val);        break;\r
 392                 case DT_RELASZ: relaSz = dynamicTab[j].d_val;   break;\r
 393                 case DT_RELAENT:        relaEntSz = dynamicTab[j].d_val;        break;\r
 394                 }\r
 395         }\r
 396         \r
 397         // Parse Relocation Entries\r
 398         if(rel && relSz)\r
 399         {\r
 400                 j = relSz / relEntSz;\r
 401                 for( i = 0; i < j; i++ )\r
 402                 {\r
 403                         ptr = (void*)(iBaseDiff + rel[i].r_offset);\r
 404                         if( !Elf_Int_DoRelocate(rel[i].r_info, ptr, *ptr, dynsymtab, (Uint)Base) ) {\r
 405                                 bFailed = 1;\r
 406                         }\r
 407                 }\r
 408         }\r
 409         // Parse Relocation Entries\r
 410         if(rela && relaSz)\r
 411         {\r
 412                 j = relaSz / relaEntSz;\r
 413                 for( i = 0; i < j; i++ )\r
 414                 {\r
 415                         ptr = (void*)(iBaseDiff + rela[i].r_offset);\r
 416                         if( !Elf_Int_DoRelocate(rela[i].r_info, ptr, rela[i].r_addend, dynsymtab, (Uint)Base) ) {\r
 417                                 bFailed = 1;\r
 418                         }\r
 419                 }\r
 420         }\r
 421         \r
 422         // === Process PLT (Procedure Linkage Table) ===\r
 423         if(plt && pltSz)\r
 424         {\r
 425                 if(pltType == DT_REL)\r
 426                 {\r
 427                         Elf32_Rel       *pltRel = plt;\r
 428                         j = pltSz / sizeof(Elf32_Rel);\r
 429                         LOG("PLT Rel - plt = %p, pltSz = %i (%i ents)", plt, pltSz, j);\r
 430                         for(i = 0; i < j; i++)\r
 431                         {\r
 432                                 ptr = (void*)(iBaseDiff + pltRel[i].r_offset);\r
 433                                 if( !Elf_Int_DoRelocate(pltRel[i].r_info, ptr, *ptr, dynsymtab, (Uint)Base) ) {\r
 434                                         bFailed = 1;\r
 435                                 }\r
 436                         }\r
 437                 }\r
 438                 else\r
 439                 {\r
 440                         Elf32_Rela      *pltRela = plt;\r
 441                         j = pltSz / sizeof(Elf32_Rela);\r
 442                         LOG("PLT RelA - plt = %p, pltSz = %i (%i ents)", plt, pltSz, j);\r
 443                         for(i=0;i<j;i++)\r
 444                         {\r
 445                                 ptr = (void*)(iBaseDiff + pltRela[i].r_offset);\r
 446                                 if( !Elf_Int_DoRelocate(pltRela[i].r_info, ptr, pltRela[i].r_addend, dynsymtab, (Uint)Base) ) {\r
 447                                         bFailed = 1;\r
 448                                 }\r
 449                         }\r
 450                 }\r
 451         }\r
 452         \r
 453         if(bFailed) {\r
 454                 LEAVE('i', 0);\r
 455                 return 0;\r
 456         }\r
 457         \r
 458         LEAVE('x', 1);\r
 459         return 1;\r
 460 }\r
 461 \r
 462 /**\r
 463  * \fn void Elf_Int_DoRelocate(Uint r_info, Uint32 *ptr, Uint32 addend, Elf32_Sym *symtab, Uint base)\r
 464  * \brief Performs a relocation\r
 465  * \param r_info        Field from relocation entry\r
 466  * \param ptr   Pointer to location of relocation\r
 467  * \param addend        Value to add to symbol\r
 468  * \param symtab        Symbol Table\r
 469  * \param base  Base of loaded binary\r
 470  */\r
 471 int Elf_Int_DoRelocate(Uint r_info, Uint32 *ptr, Uint32 addend, Elf32_Sym *symtab, Uint base)\r
 472 {\r
 473         Uint    val;\r
 474          int    type = ELF32_R_TYPE(r_info);\r
 475          int    sym = ELF32_R_SYM(r_info);\r
 476         char    *sSymName = symtab[sym].name;\r
 477         \r
 478         //LogF("Elf_Int_DoRelocate: (r_info=0x%x, ptr=0x%x, addend=0x%x, .., base=0x%x)\n",\r
 479         //      r_info, ptr, addend, base);\r
 480         \r
 481         switch( type )\r
 482         {\r
 483         // Standard 32 Bit Relocation (S+A)\r
 484         case R_386_32:\r
 485                 if( !Elf_GetSymbol((void*)base, sSymName, &val) )       // Search this binary first\r
 486                         if( !Binary_GetSymbol( sSymName, &val ) )\r
 487                                 return 0;\r
 488                 LOG("%08x R_386_32 *0x%x += 0x%x('%s')", r_info, ptr, val, sSymName);\r
 489                 *ptr = val + addend;\r
 490                 break;\r
 491                 \r
 492         // 32 Bit Relocation wrt. Offset (S+A-P)\r
 493         case R_386_PC32:\r
 494                 if( !Elf_GetSymbol( (void*)base, sSymName, &val ) )\r
 495                         if( !Binary_GetSymbol( sSymName, &val ) )\r
 496                                 return 0;\r
 497                 LOG("%08x R_386_PC32 *0x%x = 0x%x + 0x%x('%s') - 0x%x", r_info, ptr, *ptr, val, sSymName, (Uint)ptr );\r
 498                 // TODO: Check if it needs the true value of ptr or the compiled value\r
 499                 // NOTE: Testing using true value\r
 500                 *ptr = val + addend - (Uint)ptr;\r
 501                 break;\r
 502 \r
 503         // Absolute Value of a symbol (S)\r
 504         case R_386_GLOB_DAT:\r
 505                 if( !Elf_GetSymbol( (void*)base, sSymName, &val ) )\r
 506                         if( !Binary_GetSymbol( sSymName, &val ) )\r
 507                                 return 0;\r
 508                 LOG("%08x R_386_GLOB_DAT *0x%x = 0x%x (%s)", r_info, ptr, val, sSymName);\r
 509                 *ptr = val;\r
 510                 break;\r
 511         \r
 512         // Absolute Value of a symbol (S)\r
 513         case R_386_JMP_SLOT:\r
 514                 if( !Elf_GetSymbol( (void*)base, sSymName, &val ) )\r
 515                         if( !Binary_GetSymbol( sSymName, &val ) )\r
 516                                 return 0;\r
 517                 LOG("%08x R_386_JMP_SLOT *0x%x = 0x%x (%s)", r_info, ptr, val, sSymName);\r
 518                 *ptr = val;\r
 519                 break;\r
 520 \r
 521         // Base Address (B+A)\r
 522         case R_386_RELATIVE:\r
 523                 LOG("%08x R_386_RELATIVE *0x%x = 0x%x + 0x%x", r_info, ptr, base, addend);\r
 524                 *ptr = base + addend;\r
 525                 break;\r
 526                 \r
 527         default:\r
 528                 LOG("Rel 0x%x: 0x%x,%i", ptr, sym, type);\r
 529                 break;\r
 530         }\r
 531         return 1;\r
 532 }\r
 533 \r
 534 /**\r
 535  * \fn int Elf_GetSymbol(void *Base, const char *name, Uint *ret)\r
 536  * \brief Get a symbol from the loaded binary\r
 537  */\r
 538 int Elf_GetSymbol(void *Base, const char *Name, Uint *ret)\r
 539 {\r
 540         Elf32_Ehdr      *hdr = (void*)Base;\r
 541         Elf32_Sym       *symtab;\r
 542          int    nbuckets = 0;\r
 543          int    iSymCount = 0;\r
 544          int    i;\r
 545         Uint    *pBuckets;\r
 546         Uint    *pChains;\r
 547         Uint    iNameHash;\r
 548 \r
 549         if(!Base)       return 0;\r
 550 \r
 551         pBuckets = (void *) hdr->misc.HashTable;\r
 552         symtab = (void *) hdr->misc.SymTable;\r
 553         \r
 554         nbuckets = pBuckets[0];\r
 555         iSymCount = pBuckets[1];\r
 556         pBuckets = &pBuckets[2];\r
 557         pChains = &pBuckets[ nbuckets ];\r
 558         \r
 559         // Get hash\r
 560         iNameHash = Elf_Int_HashString(Name);\r
 561         iNameHash %= nbuckets;\r
 562 \r
 563         // Check Bucket\r
 564         i = pBuckets[ iNameHash ];\r
 565         if(symtab[i].shndx != SHN_UNDEF && strcmp(symtab[i].name, Name) == 0) {\r
 566                 if(ret) *ret = symtab[ i ].value;\r
 567                 return 1;\r
 568         }\r
 569         \r
 570         // Walk Chain\r
 571         while(pChains[i] != STN_UNDEF)\r
 572         {\r
 573                 i = pChains[i];\r
 574                 if(symtab[i].shndx != SHN_UNDEF && strcmp(symtab[ i ].name, Name) == 0) {\r
 575                         if(ret) *ret = symtab[ i ].value;\r
 576                         return 1;\r
 577                 }\r
 578         }\r
 579         return 0;\r
 580 }\r
 581 \r
 582 /**\r
 583  * \fn Uint Elf_Int_HashString(char *str)\r
 584  * \brief Hash a string in the ELF format\r
 585  * \param str   String to hash\r
 586  * \return Hash value\r
 587  */\r
 588 Uint Elf_Int_HashString(const char *str)\r
 589 {\r
 590         Uint    h = 0, g;\r
 591         while(*str)\r
 592         {\r
 593                 h = (h << 4) + *str++;\r
 594                 if( (g = h & 0xf0000000) )\r
 595                         h ^= g >> 24;\r
 596                 h &= ~g;\r
 597         }\r
 598         return h;\r
 599 }\r