Shared Memory and ACLs

[xwb]

I have a client process that uses shared memory created by a service. The problem is that the service is created as "Local User" so the clients are unable to access the shared memory. Even with adding a "Global\" prefix, I can't access the memory. I'm creating the shared memory as

      mHandle = CreateFileMapping (
         (HANDLE) 0xFFFFFFFF,           // Use system buffering
         (LPSECURITY_ATTRIBUTES) 0,
         PAGE_READWRITE,                // Protection
         0,                             // filesize high dword
         mFileSize,                      // filesize low dword
         name);                         // Name

What it boils down to is I have to fill in the LPSECURITY_ATTRIBUTES for the "Everyone" user. I've been playing with all sorts of combinations for the last 3 hours and getting nowhere. This is the basic framework I'm using

      SECURITY_DESCRIPTOR* sd = new SECURITY_DESCRIPTOR();
      InitializeSecurityDescriptor (sd, SECURITY_DESCRIPTOR_REVISION);
      // Have tried all sorts of permutations on the contents of sd

      SECURITY_ATTRIBUTES* sa = new SECURITY_ATTRIBUTES;
      sa->nLength = sizeof (*sa);
      sa->bInheritHandle = FALSE;
      sa->lpSecurityDescriptor = sd;
      std::string name = "Global\\";
      name += (in_name == 0? SMBaseName: in_name);
      mHandle = CreateFileMapping (
         (HANDLE) 0xFFFFFFFF,           // Use system buffering
         sa,
         PAGE_READWRITE,           // Protection
         0,                             // filesize high dword
         mFileSize,                     // filesize low dword
         name.c_str());                 // Name

Any simple examples on what to put into sd to represent the "Everyone" user would be great.

 

[xwb]

Found the answer in

http://msdn.microsoft.com/en-us/library/aa446595(VS.85).aspx