Problem - Kevin Tafuro

Discussion
The Win32 API function LookupAccountName( ) is used to find the SID that corresponds
to a name. You can use it to obtain information about a name on either the
local system or a remote system. While it might seem that mapping a name to a SID
is a simple operation, LookupAccountName( ) actually requires a large number of arguments
to allow it to complete its work.
LookupAccountName( ) has the following signature:
BOOL LookupAccountName(LPCTSTR lpSystemName, LPCTSTR lpAccountName, PSID Sid,
LPDWORD cbSid, LPTSTR ReferencedDomainName,
LPDWORD cbReferencedDomainName, PSID_NAME_USE peUse);
This function has the following arguments:
lpSystemName
String representing the name of the remote system on which to look up the
name. If you specify this argument as NULL, the lookup will be done on the local
system.
lpAccountName
String representing the name of the user or group to look up. This argument may
not be specified as NULL.
Sid
Buffer into which the SID will be written. Initially, you may specify this argument
as NULL to determine how large a buffer is required to hold the SID.
cbSid
Pointer to an integer that both specifies the size of the buffer to receive the SID,
and receives the size of the buffer required for the SID.
ReferencedDomainName
Buffer into which the domain name where the user or group name was found is
to be written. Initially, you may specify this argument as NULL to determine how
large a buffer is required to hold the domain name.
cbReferencedDomainName
Pointer to an integer that both specifies the size of the buffer to receive the
domain name, and receives the size of the buffer required for the domain name.
peUse
Pointer to an enumeration that receives the type of SID to which the looked-up
name corresponds. The most commonly returned values are SidTypeUser (1) and
SidTypeGroup (2).
The following function, SpcLookupName( ), is essentially a wrapper around
LookupAccountName( ). It handles the nuances of performing user and group name
lookup, including allocating the necessary buffers and error conditions. If the name
is successfully found, the return will be a pointer to a dynamically allocated SID
structure, which you must later free using LocalFree( ). If the name could not be
376 | Chapter 8: Authentication and Key Exchange
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