reactos/ntoskrnl/ps/cid.c

   1 /* $Id$
   2  *
   3  * COPYRIGHT:       See COPYING in the top level directory
   4  * PROJECT:         ReactOS kernel
   5  * FILE:            ntoskrnl/ps/cid.c
   6  * PURPOSE:         Client ID (CID) management
   7  *
   8  * PROGRAMMERS:     Thomas Weidenmueller <w3seek@reactos.com>
   9  */
  10
  11 /* INCLUDES ******************************************************************/
  12
  13 #include <ntoskrnl.h>
  14 #define NDEBUG
  15 #include <internal/debug.h>
  16
  17 /* GLOBALS ******************************************************************/
  18
  19 PHANDLE_TABLE PspCidTable = NULL;
  20
  21 #define TAG_CIDOBJECT TAG('C', 'I', 'D', 'O')
  22
  23 #define CID_FLAG_PROCESS 0x1
  24 #define CID_FLAG_THREAD 0x2
  25 #define CID_FLAGS_MASK (CID_FLAG_PROCESS | CID_FLAG_THREAD)
  26
  27 /* FUNCTIONS *****************************************************************/
  28
  29 VOID INIT_FUNCTION
  30 PsInitClientIDManagment(VOID)
  31 {
  32   PspCidTable = ExCreateHandleTable(NULL);
  33   ASSERT(PspCidTable);
  34 }
  35
  36 NTSTATUS
  37 PsCreateCidHandle(PVOID Object, POBJECT_TYPE ObjectType, PHANDLE Handle)
  38 {
  39   HANDLE_TABLE_ENTRY NewEntry;
  40   LONG ExHandle;
  41
  42   PAGED_CODE();
  43
  44   NewEntry.u1.Object = Object;
  45   if(ObjectType == PsThreadType)
  46     NewEntry.u2.GrantedAccess = CID_FLAG_THREAD;
  47   else if(ObjectType == PsProcessType)
  48     NewEntry.u2.GrantedAccess = CID_FLAG_PROCESS;
  49   else
  50   {
  51     DPRINT1("Can't create CID handles for %wZ objects\n", &ObjectType->TypeName);
  52     KEBUGCHECK(0);
  53   }
  54
  55   ExHandle = ExCreateHandle(PspCidTable,
  56                             &NewEntry);
  57   if(ExHandle != EX_INVALID_HANDLE)
  58   {
  59     *Handle = EX_HANDLE_TO_HANDLE(ExHandle);
  60     return STATUS_SUCCESS;
  61   }
  62
  63   return STATUS_UNSUCCESSFUL;
  64 }
  65
  66 NTSTATUS
  67 PsDeleteCidHandle(HANDLE CidHandle, POBJECT_TYPE ObjectType)
  68 {
  69   PHANDLE_TABLE_ENTRY Entry;
  70   LONG ExHandle = HANDLE_TO_EX_HANDLE(CidHandle);
  71
  72   PAGED_CODE();
  73
  74   Entry = ExMapHandleToPointer(PspCidTable,
  75                                ExHandle);
  76   if(Entry != NULL)
  77   {
  78     if((ObjectType == PsThreadType && ((Entry->u2.GrantedAccess & CID_FLAGS_MASK) == CID_FLAG_THREAD)) ||
  79        (ObjectType == PsProcessType && ((Entry->u2.GrantedAccess & CID_FLAGS_MASK) == CID_FLAG_PROCESS)))
  80     {
  81       ExDestroyHandleByEntry(PspCidTable,
  82                              Entry,
  83                              ExHandle);
  84       return STATUS_SUCCESS;
  85     }
  86     else
  87     {
  88       ExUnlockHandleTableEntry(PspCidTable,
  89                                Entry);
  90       return STATUS_OBJECT_TYPE_MISMATCH;
  91     }
  92   }
  93
  94   return STATUS_INVALID_HANDLE;
  95 }
  96
  97 PHANDLE_TABLE_ENTRY
  98 PsLookupCidHandle(HANDLE CidHandle, POBJECT_TYPE ObjectType, PVOID *Object)
  99 {
 100   PHANDLE_TABLE_ENTRY Entry;
 101
 102   PAGED_CODE();
 103
 104   KeEnterCriticalRegion();
 105
 106   Entry = ExMapHandleToPointer(PspCidTable,
 107                                HANDLE_TO_EX_HANDLE(CidHandle));
 108   if(Entry != NULL)
 109   {
 110     if((ObjectType == PsProcessType && ((Entry->u2.GrantedAccess & CID_FLAGS_MASK) == CID_FLAG_PROCESS)) ||
 111        (ObjectType == PsThreadType && ((Entry->u2.GrantedAccess & CID_FLAGS_MASK) == CID_FLAG_THREAD)))
 112     {
 113       *Object = Entry->u1.Object;
 114       return Entry;
 115     }
 116     else
 117     {
 118       DPRINT1("CID Obj type mismatch handle 0x%x %wZ vs 0x%x\n", CidHandle,
 119               &ObjectType->TypeName, Entry->u2.GrantedAccess);
 120       ExUnlockHandleTableEntry(PspCidTable,
 121                                Entry);
 122       KEBUGCHECK(0);
 123     }
 124   }
 125
 126   KeLeaveCriticalRegion();
 127
 128   return NULL;
 129 }
 130
 131 /*
 132  * @implemented
 133  */
 134 NTSTATUS STDCALL
 135 PsLookupProcessThreadByCid(IN PCLIENT_ID Cid,
 136                            OUT PEPROCESS *Process OPTIONAL,
 137                            OUT PETHREAD *Thread)
 138 {
 139   PHANDLE_TABLE_ENTRY CidEntry;
 140   PETHREAD FoundThread;
 141
 142   PAGED_CODE();
 143
 144   ASSERT(Thread);
 145   ASSERT(Cid);
 146
 147   CidEntry = PsLookupCidHandle(Cid->UniqueThread, PsThreadType, (PVOID*)&FoundThread);
 148   if(CidEntry != NULL)
 149   {
 150     ObReferenceObject(FoundThread);
 151
 152     PsUnlockCidHandle(CidEntry);
 153
 154     if(Process != NULL)
 155     {
 156       *Process = FoundThread->ThreadsProcess;
 157     }
 158     *Thread = FoundThread;
 159     return STATUS_SUCCESS;
 160   }
 161
 162   return STATUS_INVALID_PARAMETER;
 163 }
 164
 165
 166 /*
 167  * @implemented
 168  */
 169 NTSTATUS STDCALL
 170 PsLookupThreadByThreadId(IN HANDLE ThreadId,
 171                          OUT PETHREAD *Thread)
 172 {
 173   PHANDLE_TABLE_ENTRY CidEntry;
 174   PETHREAD FoundThread;
 175
 176   PAGED_CODE();
 177
 178   ASSERT(Thread);
 179
 180   CidEntry = PsLookupCidHandle(ThreadId, PsThreadType, (PVOID*)&FoundThread);
 181   if(CidEntry != NULL)
 182   {
 183     ObReferenceObject(FoundThread);
 184
 185     PsUnlockCidHandle(CidEntry);
 186
 187     *Thread = FoundThread;
 188     return STATUS_SUCCESS;
 189   }
 190
 191   return STATUS_INVALID_PARAMETER;
 192 }
 193
 194 VOID
 195 PsUnlockCidHandle(PHANDLE_TABLE_ENTRY CidEntry)
 196 {
 197   PAGED_CODE();
 198
 199   ExUnlockHandleTableEntry(PspCidTable,
 200                            CidEntry);
 201   KeLeaveCriticalRegion();
 202 }
 203
 204 /* EOF */