src/WINNT/client_config/isadmin.cpp

   1 /*
   2  * Copyright 2000, International Business Machines Corporation and others.
   3  * All Rights Reserved.
   4  *
   5  * This software has been released under the terms of the IBM Public
   6  * License.  For details, see the LICENSE file in the top-level source
   7  * directory or online at http://www.openafs.org/dl/license10.html
   8  */
   9
  10 #include <winsock2.h>
  11 #include <ws2tcpip.h>
  12
  13 extern "C" {
  14 #include <afs/param.h>
  15 #include <afs/stds.h>
  16 }
  17
  18 #include <windows.h>
  19 #include <WINNT/TaLocale.h>
  20
  21
  22 /*
  23  * ISWINNT ____________________________________________________________________
  24  *
  25  */
  26
  27 BOOL IsWindowsNT (void)
  28 {
  29    static BOOL fChecked = FALSE;
  30    static BOOL fIsWinNT = FALSE;
  31
  32    if (!fChecked)
  33       {
  34       fChecked = TRUE;
  35
  36       OSVERSIONINFO Version;
  37       memset (&Version, 0x00, sizeof(Version));
  38       Version.dwOSVersionInfoSize = sizeof(Version);
  39
  40       if (GetVersionEx (&Version))
  41          {
  42          if (Version.dwPlatformId == VER_PLATFORM_WIN32_NT)
  43             fIsWinNT = TRUE;
  44          }
  45       }
  46
  47    return fIsWinNT;
  48 }
  49
  50
  51 /*
  52  * ISADMIN ____________________________________________________________________
  53  *
  54  */
  55
  56 #define AFSCLIENT_ADMIN_GROUPNAME "AFS Client Admins"
  57
  58 BOOL IsAdmin (void)
  59 {
  60     static BOOL fAdmin = FALSE;
  61     static BOOL fTested = FALSE;
  62
  63     if (!fTested)
  64     {
  65         /* Obtain the SID for the AFS client admin group.  If the group does
  66          * not exist, then assume we have AFS client admin privileges.
  67          */
  68         PSID psidAdmin = NULL;
  69         DWORD dwSize, dwSize2;
  70         char pszAdminGroup[ MAX_COMPUTERNAME_LENGTH + sizeof(AFSCLIENT_ADMIN_GROUPNAME) + 2 ];
  71         char *pszRefDomain = NULL;
  72         SID_NAME_USE snu = SidTypeGroup;
  73
  74         dwSize = sizeof(pszAdminGroup);
  75
  76         if (!GetComputerName(pszAdminGroup, &dwSize)) {
  77             /* Can't get computer name.  We return false in this case.
  78                Retain fAdmin and fTested. This shouldn't happen.*/
  79             return FALSE;
  80         }
  81
  82         dwSize = 0;
  83         dwSize2 = 0;
  84
  85         strcat(pszAdminGroup,"\\");
  86         strcat(pszAdminGroup, AFSCLIENT_ADMIN_GROUPNAME);
  87
  88         LookupAccountName(NULL, pszAdminGroup, NULL, &dwSize, NULL, &dwSize2, &snu);
  89         /* that should always fail. */
  90
  91         if (GetLastError() != ERROR_INSUFFICIENT_BUFFER) {
  92             /* if we can't find the group, then we allow the operation */
  93             fAdmin = TRUE;
  94             return TRUE;
  95         }
  96
  97         if (dwSize == 0 || dwSize2 == 0) {
  98             /* Paranoia */
  99             fAdmin = TRUE;
 100             return TRUE;
 101         }
 102
 103         psidAdmin = (PSID)malloc(dwSize); memset(psidAdmin,0,dwSize);
 104         pszRefDomain = (char *)malloc(dwSize2);
 105
 106         if (!LookupAccountName(NULL, pszAdminGroup, psidAdmin, &dwSize, pszRefDomain, &dwSize2, &snu)) {
 107             /* We can't lookup the group now even though we looked it up earlier.
 108                Could this happen? */
 109             fAdmin = TRUE;
 110         } else {
 111             /* Then open our current ProcessToken */
 112             HANDLE hToken;
 113
 114             if (OpenProcessToken (GetCurrentProcess(), TOKEN_QUERY, &hToken))
 115             {
 116
 117                 if (!CheckTokenMembership(hToken, psidAdmin, &fAdmin)) {
 118                     /* We'll have to allocate a chunk of memory to store the list of
 119                      * groups to which this user belongs; find out how much memory
 120                      * we'll need.
 121                      */
 122                     DWORD dwSize = 0;
 123                     PTOKEN_GROUPS pGroups;
 124
 125                     GetTokenInformation (hToken, TokenGroups, NULL, dwSize, &dwSize);
 126
 127                     pGroups = (PTOKEN_GROUPS)malloc(dwSize);
 128
 129                     /* Allocate that buffer, and read in the list of groups. */
 130                     if (GetTokenInformation (hToken, TokenGroups, pGroups, dwSize, &dwSize))
 131                     {
 132                         /* Look through the list of group SIDs and see if any of them
 133                          * matches the AFS Client Admin group SID.
 134                          */
 135                         size_t iGroup = 0;
 136                         for (; (!fAdmin) && (iGroup < pGroups->GroupCount); ++iGroup)
 137                         {
 138                             if (EqualSid (psidAdmin, pGroups->Groups[ iGroup ].Sid)) {
 139                                 fAdmin = TRUE;
 140                             }
 141                         }
 142                     }
 143
 144                     if (pGroups)
 145                         free(pGroups);
 146                 }
 147
 148                 /* if do not have permission because we were not explicitly listed
 149                  * in the Admin Client Group let's see if we are the SYSTEM account
 150                  */
 151                 if (!fAdmin) {
 152                     PTOKEN_USER pTokenUser;
 153                     SID_IDENTIFIER_AUTHORITY SIDAuth = SECURITY_NT_AUTHORITY;
 154                     PSID pSidLocalSystem = 0;
 155                     DWORD gle;
 156
 157                     GetTokenInformation(hToken, TokenUser, NULL, 0, &dwSize);
 158
 159                     pTokenUser = (PTOKEN_USER)malloc(dwSize);
 160
 161                     if (!GetTokenInformation(hToken, TokenUser, pTokenUser, dwSize, &dwSize))
 162                         gle = GetLastError();
 163
 164                     if (AllocateAndInitializeSid( &SIDAuth, 1,
 165                                                   SECURITY_LOCAL_SYSTEM_RID,
 166                                                   0, 0, 0, 0, 0, 0, 0,
 167                                                   &pSidLocalSystem))
 168                     {
 169                         if (EqualSid(pTokenUser->User.Sid, pSidLocalSystem)) {
 170                             fAdmin = TRUE;
 171                         }
 172
 173                         FreeSid(pSidLocalSystem);
 174                     }
 175
 176                     if ( pTokenUser )
 177                         free(pTokenUser);
 178                 }
 179             }
 180         }
 181
 182         free(psidAdmin);
 183         free(pszRefDomain);
 184
 185         fTested = TRUE;
 186     }
 187
 188     return fAdmin;
 189 }
 190