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