misc.c

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/*
 *  ReactOS kernel
 *  Copyright (C) 2004 ReactOS Team
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
/* $Id: misc.c 43790 2009-10-27 10:34:16Z dgorbachev $
 *
 * COPYRIGHT:       See COPYING in the top level directory
 * PROJECT:         ReactOS system libraries
 * FILE:            lib/userenv/misc.c
 * PURPOSE:         User profile code
 * PROGRAMMER:      Eric Kohl
 */

#include <precomp.h>

#define NDEBUG
#include <debug.h>

static SID_IDENTIFIER_AUTHORITY LocalSystemAuthority = {SECURITY_NT_AUTHORITY};
static SID_IDENTIFIER_AUTHORITY WorldAuthority = {SECURITY_WORLD_SID_AUTHORITY};

/* FUNCTIONS ***************************************************************/

LPWSTR
AppendBackslash (LPWSTR String)
{
  ULONG Length;

  Length = lstrlenW (String);
  if (String[Length - 1] != L'\\')
    {
      String[Length] = L'\\';
      Length++;
      String[Length] = (WCHAR)0;
    }

  return &String[Length];
}


BOOL
GetUserSidFromToken (HANDLE hToken,
             PUNICODE_STRING SidString)
{
  PSID_AND_ATTRIBUTES SidBuffer, nsb;
  ULONG Length;
  NTSTATUS Status;

  Length = 256;
  SidBuffer = LocalAlloc (LMEM_FIXED,
              Length);
  if (SidBuffer == NULL)
    return FALSE;

  Status = NtQueryInformationToken (hToken,
                    TokenUser,
                    (PVOID)SidBuffer,
                    Length,
                    &Length);
  if (Status == STATUS_BUFFER_TOO_SMALL)
    {
      nsb = LocalReAlloc (SidBuffer,
                          Length,
                          LMEM_MOVEABLE);
      if (nsb == NULL)
        {
          LocalFree((HLOCAL)SidBuffer);
          return FALSE;
        }

      SidBuffer = nsb;
      Status = NtQueryInformationToken (hToken,
                    TokenUser,
                    (PVOID)SidBuffer,
                    Length,
                    &Length);
    }

  if (!NT_SUCCESS (Status))
    {
      LocalFree ((HLOCAL)SidBuffer);
      SetLastError (RtlNtStatusToDosError (Status));
      return FALSE;
    }

  DPRINT ("SidLength: %lu\n", RtlLengthSid (SidBuffer[0].Sid));

  Status = RtlConvertSidToUnicodeString (SidString,
                     SidBuffer[0].Sid,
                     TRUE);

  LocalFree ((HLOCAL)SidBuffer);

  if (!NT_SUCCESS (Status))
    {
      SetLastError (RtlNtStatusToDosError (Status));
      return FALSE;
    }

  DPRINT ("SidString.Length: %lu\n", SidString->Length);
  DPRINT ("SidString.MaximumLength: %lu\n", SidString->MaximumLength);
  DPRINT ("SidString: '%wZ'\n", SidString);

  return TRUE;
}

PSECURITY_DESCRIPTOR
CreateDefaultSecurityDescriptor(VOID)
{
    PSID LocalSystemSid = NULL;
    PSID AdministratorsSid = NULL;
    PSID EveryoneSid = NULL;
    PACL Dacl;
    DWORD DaclSize;
    PSECURITY_DESCRIPTOR pSD = NULL;

    /* create the SYSTEM, Administrators and Everyone SIDs */
    if (!AllocateAndInitializeSid(&LocalSystemAuthority,
                                  1,
                                  SECURITY_LOCAL_SYSTEM_RID,
                                  0,
                                  0,
                                  0,
                                  0,
                                  0,
                                  0,
                                  0,
                                  &LocalSystemSid) ||
        !AllocateAndInitializeSid(&LocalSystemAuthority,
                                  2,
                                  SECURITY_BUILTIN_DOMAIN_RID,
                                  DOMAIN_ALIAS_RID_ADMINS,
                                  0,
                                  0,
                                  0,
                                  0,
                                  0,
                                  0,
                                  &AdministratorsSid) ||
        !AllocateAndInitializeSid(&WorldAuthority,
                                  1,
                                  SECURITY_WORLD_RID,
                                  0,
                                  0,
                                  0,
                                  0,
                                  0,
                                  0,
                                  0,
                                  &EveryoneSid))
    {
        DPRINT1("Failed initializing the SIDs for the default security descriptor (0x%p, 0x%p, 0x%p)\n",
                LocalSystemSid, AdministratorsSid, EveryoneSid);
        goto Cleanup;
    }

    /* allocate the security descriptor and DACL */
    DaclSize = sizeof(ACL) +
               ((GetLengthSid(LocalSystemSid) +
                 GetLengthSid(AdministratorsSid) +
                 GetLengthSid(EveryoneSid)) +
                (3 * FIELD_OFFSET(ACCESS_ALLOWED_ACE,
                                  SidStart)));

    pSD = (PSECURITY_DESCRIPTOR)LocalAlloc(LMEM_FIXED,
                                           (SIZE_T)DaclSize + sizeof(SECURITY_DESCRIPTOR));
    if (pSD == NULL)
    {
        DPRINT1("Failed to allocate the default security descriptor and ACL\n");
        goto Cleanup;
    }

    if (!InitializeSecurityDescriptor(pSD,
                                      SECURITY_DESCRIPTOR_REVISION))
    {
        DPRINT1("Failed to initialize the default security descriptor\n");
        goto Cleanup;
    }

    /* initialize and build the DACL */
    Dacl = (PACL)((ULONG_PTR)pSD + sizeof(SECURITY_DESCRIPTOR));
    if (!InitializeAcl(Dacl,
                       (DWORD)DaclSize,
                       ACL_REVISION))
    {
        DPRINT1("Failed to initialize the DACL of the default security descriptor\n");
        goto Cleanup;
    }

    /* add the SYSTEM Ace */
    if (!AddAccessAllowedAce(Dacl,
                             ACL_REVISION,
                             GENERIC_ALL,
                             LocalSystemSid))
    {
        DPRINT1("Failed to add the SYSTEM ACE\n");
        goto Cleanup;
    }

    /* add the Administrators Ace */
    if (!AddAccessAllowedAce(Dacl,
                             ACL_REVISION,
                             GENERIC_ALL,
                             AdministratorsSid))
    {
        DPRINT1("Failed to add the Administrators ACE\n");
        goto Cleanup;
    }

    /* add the Everyone Ace */
    if (!AddAccessAllowedAce(Dacl,
                             ACL_REVISION,
                             GENERIC_EXECUTE,
                             EveryoneSid))
    {
        DPRINT1("Failed to add the Everyone ACE\n");
        goto Cleanup;
    }

    /* set the DACL */
    if (!SetSecurityDescriptorDacl(pSD,
                                   TRUE,
                                   Dacl,
                                   FALSE))
    {
        DPRINT1("Failed to set the DACL of the default security descriptor\n");

Cleanup:
        if (pSD != NULL)
        {
            LocalFree((HLOCAL)pSD);
            pSD = NULL;
        }
    }

    if (LocalSystemSid != NULL)
    {
        FreeSid(LocalSystemSid);
    }
    if (AdministratorsSid != NULL)
    {
        FreeSid(AdministratorsSid);
    }
    if (EveryoneSid != NULL)
    {
        FreeSid(EveryoneSid);
    }

    return pSD;
}

/* Dynamic DLL loading interface **********************************************/

/* OLE32.DLL import table */
DYN_MODULE DynOle32 =
{
  L"ole32.dll",
  {
    "CoInitialize",
    "CoCreateInstance",
    "CoUninitialize",
    NULL
  }
};


/*
 * Use this function to load functions from other modules. We cannot statically
 * link to e.g. ole32.dll because those dlls would get loaded on startup with
 * winlogon and they may try to register classes etc when not even a window station
 * has been created!
 */
BOOL
LoadDynamicImports(PDYN_MODULE Module, PDYN_FUNCS DynFuncs)
{
  LPSTR *fname;
  PVOID *fn;

  ZeroMemory(DynFuncs, sizeof(DYN_FUNCS));

  DynFuncs->hModule = LoadLibraryW(Module->Library);
  if (!DynFuncs->hModule)
    {
      return FALSE;
    }

  fn = &DynFuncs->fn.foo;

  /* load the imports */
  for (fname = Module->Functions; *fname != NULL; fname++)
    {
      *fn = GetProcAddress(DynFuncs->hModule, *fname);
      if (*fn == NULL)
        {
          FreeLibrary(DynFuncs->hModule);
          DynFuncs->hModule = (HMODULE)0;

          return FALSE;
        }

      fn++;
    }

  return TRUE;
}


VOID
UnloadDynamicImports(PDYN_FUNCS DynFuncs)
{
  if (DynFuncs->hModule)
    {
      FreeLibrary(DynFuncs->hModule);
      DynFuncs->hModule = (HMODULE)0;
    }
}

/* EOF */