SecFile Sample: File Security

Click to open or copy the files for the SecFile sample.

The Secfile sample demonstrates the following security-related activities:

• Constructing well-known security identifiers (SIDs)
  
  
• Obtaining the current user's SID
  
  
• Building a discretionary access control list (DACL)
  
  
• Building a security descriptor (SD)

Use this sample in conjunction with the Win32 Programmer's Reference. Looking at the documentation and an example function call should make both the documentation and the sample more clear.

This sample only works on an NTFS partition. No other file system supports security. You can use File Manager or the Windows Explorer to check the security on the file after you run the sample. One thing you may notice is that the user "Everyone" has "Special" access instead of "Read" access. That's because the system considers "Read" access to include both read and execute rights. To modify the sample to give "Everyone" "Read" access, change the statement:

#define WORLD_ACCESS GENERIC_READ

to the following:

#define WORLD_ACCESS (GENERIC_READ | GENERIC_EXECUTE)

Building SDK Samples

This sample uses the following keywords:

addaccessallowedace; allocateandinitializesid; closehandle; copysid; createfile; createworldsid; exitprocess; fprintf; freesid; getcurrentprocess; getlasterror; getlasterrortext; getlengthsid; getprocessheap; gettokeninformation; getusersid; heapalloc; heapfree; initializeacl; initializesecuritydescriptor; lstrlen; openprocesstoken; perr; setsecuritydescriptordacl; writefile