Extracting the SID from an ACE

Last reviewed: November 2, 1995
Article ID: Q102101

The information in this article applies to:

Microsoft Win32 Application Programming Interface (API) included with:
```
    - Microsoft Windows NT versions 3.1 and 3.5
```

SUMMARY

To access the security identifier (SID) contained in an access control entry (ACE), the following syntax can be used:

   PSID pSID;

   if((((PACE_HEADER)pTempAce)->AceType) == ACCESS_ALLOWED_ACE_TYPE)
   {
      pSID=(PSID)&((PACCESS_ALLOWED_ACE)pTempAce)->SidStart;
   }

MORE INFORMATION

The "if" statement checks the type of ACE, which is one of the following values:

   ACCESS_ALLOWED_ACE_TYPE
   ACCESS_DENIED_ACE_TYPE
   SYSTEM_AUDIT_ACE_TYPE

The conditional statement casts pTempAce (the pointer to the ACE) to a PACCESS_ALLOWED_ACE structure. The address of the SidStart member is then cast to a PSID and assigned to the pSID variable. pSID can now be used with any Win32 Security application programming interface (API) that takes a PSID as a parameter.

Additional reference words: 3.10 3.50
KBCategory: kbprg
KBSubcategory: BseSecurity

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.

Last reviewed: November 2, 1995
© 1998 Microsoft Corporation. All rights reserved. Terms of Use.