ntoskrnl/ldr/rtl.c

   1 /* $Id$
   2  *
   3  * COPYRIGHT:       See COPYING in the top level directory
   4  * PROJECT:         ReactOS kernel
   5  * FILE:            ntoskrnl/ldr/loader.c
   6  * PURPOSE:         Loader utilities
   7  * PROGRAMMERS:     Jean Michault
   8  *                  Rex Jolliff (rex@lvcablemodem.com)
   9  */
  10
  11 /* INCLUDES *****************************************************************/
  12
  13 #include <ddk/ntddk.h>
  14 #include <internal/module.h>
  15 #include <internal/ntoskrnl.h>
  16 #include <internal/ob.h>
  17 #include <internal/ps.h>
  18 #include <internal/ldr.h>
  19
  20 #define NDEBUG
  21 #include <internal/debug.h>
  22
  23 /* FUNCTIONS ****************************************************************/
  24
  25
  26 /*
  27  * @implemented
  28  */
  29 PIMAGE_NT_HEADERS STDCALL
  30 RtlImageNtHeader (IN PVOID BaseAddress)
  31 {
  32    PIMAGE_DOS_HEADER DosHeader;
  33    PIMAGE_NT_HEADERS NTHeaders;
  34
  35    DosHeader = (PIMAGE_DOS_HEADER)BaseAddress;
  36    NTHeaders = (PIMAGE_NT_HEADERS)(BaseAddress + DosHeader->e_lfanew);
  37    if ((DosHeader->e_magic != IMAGE_DOS_MAGIC)
  38        || (DosHeader->e_lfanew == 0L)
  39        || (*(PULONG) NTHeaders != IMAGE_PE_MAGIC))
  40      {
  41         return(NULL);
  42      }
  43    return(NTHeaders);
  44 }
  45
  46
  47 /*
  48  * @implemented
  49  */
  50 PVOID STDCALL
  51 RtlImageDirectoryEntryToData (IN PVOID  BaseAddress,
  52                               IN BOOLEAN        ImageLoaded,
  53                               IN ULONG  Directory,
  54                               OUT PULONG        Size)
  55 {
  56         PIMAGE_NT_HEADERS NtHeader;
  57         PIMAGE_SECTION_HEADER SectionHeader;
  58         ULONG Va;
  59         ULONG Count;
  60
  61         NtHeader = RtlImageNtHeader (BaseAddress);
  62         if (NtHeader == NULL)
  63                 return NULL;
  64
  65         if (Directory >= NtHeader->OptionalHeader.NumberOfRvaAndSizes)
  66                 return NULL;
  67
  68         Va = NtHeader->OptionalHeader.DataDirectory[Directory].VirtualAddress;
  69         if (Va == 0)
  70                 return NULL;
  71
  72         if (Size)
  73                 *Size = NtHeader->OptionalHeader.DataDirectory[Directory].Size;
  74
  75         if (ImageLoaded)
  76                 return (PVOID)(BaseAddress + Va);
  77
  78         /* image mapped as ordinary file, we must find raw pointer */
  79         SectionHeader = (PIMAGE_SECTION_HEADER)(NtHeader + 1);
  80         Count = NtHeader->FileHeader.NumberOfSections;
  81         while (Count--)
  82         {
  83                 if (SectionHeader->VirtualAddress == Va)
  84                         return (PVOID)(BaseAddress + SectionHeader->PointerToRawData);
  85                 SectionHeader++;
  86         }
  87
  88         return NULL;
  89 }
  90
  91
  92 PIMAGE_SECTION_HEADER
  93 STDCALL
  94 RtlImageRvaToSection (
  95         PIMAGE_NT_HEADERS       NtHeader,
  96         PVOID                   BaseAddress,
  97         ULONG                   Rva
  98         )
  99 {
 100         PIMAGE_SECTION_HEADER Section;
 101         ULONG Va;
 102         ULONG Count;
 103
 104         Count = NtHeader->FileHeader.NumberOfSections;
 105         Section = (PIMAGE_SECTION_HEADER)((ULONG)&NtHeader->OptionalHeader +
 106                                           NtHeader->FileHeader.SizeOfOptionalHeader);
 107         while (Count)
 108         {
 109                 Va = Section->VirtualAddress;
 110                 if ((Va <= Rva) &&
 111                     (Rva < Va + Section->SizeOfRawData))
 112                         return Section;
 113                 Section++;
 114         }
 115         return NULL;
 116 }
 117
 118
 119 ULONG
 120 STDCALL
 121 RtlImageRvaToVa (
 122         PIMAGE_NT_HEADERS       NtHeader,
 123         PVOID                   BaseAddress,
 124         ULONG                   Rva,
 125         PIMAGE_SECTION_HEADER   *SectionHeader
 126         )
 127 {
 128         PIMAGE_SECTION_HEADER Section = NULL;
 129
 130         if (SectionHeader)
 131                 Section = *SectionHeader;
 132
 133         if (Section == NULL ||
 134             Rva < Section->VirtualAddress ||
 135             Rva >= Section->VirtualAddress + Section->SizeOfRawData)
 136         {
 137                 Section = RtlImageRvaToSection (NtHeader, BaseAddress, Rva);
 138                 if (Section == NULL)
 139                         return 0;
 140
 141                 if (SectionHeader)
 142                         *SectionHeader = Section;
 143         }
 144
 145         return (ULONG)(BaseAddress +
 146                        Rva +
 147                        Section->PointerToRawData -
 148                        Section->VirtualAddress);
 149 }
 150
 151 #define RVA(m, b) ((ULONG)b + m)
 152
 153 NTSTATUS STDCALL
 154 LdrGetProcedureAddress (IN PVOID BaseAddress,
 155                         IN PANSI_STRING Name,
 156                         IN ULONG Ordinal,
 157                         OUT PVOID *ProcedureAddress)
 158 {
 159    PIMAGE_EXPORT_DIRECTORY ExportDir;
 160    PUSHORT OrdinalPtr;
 161    PULONG NamePtr;
 162    PULONG AddressPtr;
 163    ULONG i = 0;
 164
 165    /* get the pointer to the export directory */
 166    ExportDir = (PIMAGE_EXPORT_DIRECTORY)
 167         RtlImageDirectoryEntryToData (BaseAddress, TRUE,
 168                                       IMAGE_DIRECTORY_ENTRY_EXPORT, &i);
 169
 170    if (!ExportDir || !i || !ProcedureAddress)
 171      {
 172         return(STATUS_INVALID_PARAMETER);
 173      }
 174
 175    AddressPtr = (PULONG)RVA(BaseAddress, ExportDir->AddressOfFunctions);
 176    if (Name && Name->Length)
 177      {
 178        ULONG minn, maxn;
 179
 180         /* by name */
 181        OrdinalPtr =
 182          (PUSHORT)RVA(BaseAddress, ExportDir->AddressOfNameOrdinals);
 183        NamePtr = (PULONG)RVA(BaseAddress, ExportDir->AddressOfNames);
 184
 185         minn = 0; maxn = ExportDir->NumberOfNames;
 186         while (minn <= maxn)
 187           {
 188             ULONG mid;
 189             LONG res;
 190
 191             mid = (minn + maxn) / 2;
 192             res = _strnicmp(Name->Buffer, (PCH)RVA(BaseAddress, NamePtr[mid]),
 193                             Name->Length);
 194             if (res == 0)
 195               {
 196                 *ProcedureAddress =
 197                   (PVOID)RVA(BaseAddress, AddressPtr[OrdinalPtr[mid]]);
 198                 return(STATUS_SUCCESS);
 199               }
 200             else if (res > 0)
 201               {
 202                 maxn = mid - 1;
 203               }
 204             else
 205               {
 206                 minn = mid + 1;
 207               }
 208           }
 209
 210         for (i = 0; i < ExportDir->NumberOfNames; i++, NamePtr++, OrdinalPtr++)
 211           {
 212              if (!_strnicmp(Name->Buffer,
 213                             (char*)(BaseAddress + *NamePtr), Name->Length))
 214                {
 215                   *ProcedureAddress =
 216                     (PVOID)((ULONG)BaseAddress +
 217                             (ULONG)AddressPtr[*OrdinalPtr]);
 218                   return STATUS_SUCCESS;
 219                }
 220           }
 221         CPRINT("LdrGetProcedureAddress: Can't resolve symbol '%Z'\n", Name);
 222      }
 223    else
 224      {
 225         /* by ordinal */
 226         Ordinal &= 0x0000FFFF;
 227         if (Ordinal - ExportDir->Base < ExportDir->NumberOfFunctions)
 228           {
 229              *ProcedureAddress =
 230                (PVOID)((ULONG)BaseAddress +
 231                        (ULONG)AddressPtr[Ordinal - ExportDir->Base]);
 232              return STATUS_SUCCESS;
 233           }
 234         CPRINT("LdrGetProcedureAddress: Can't resolve symbol @%d\n",
 235                  Ordinal);
 236   }
 237
 238    return STATUS_PROCEDURE_NOT_FOUND;
 239 }
 240
 241 /* EOF */