The HCRYPTHASH data type is used to represent handles to a hash object. These handles are used to indicate to the CSP module which hash is being used in a particular operation. The CSP module does not allow direct manipulation of the hash values. Instead, the user manipulates the hash values through the hash handle.
HCRYPTHASH is defined in the WINCRYPT.H header file as:
typedef unsigned long HCRYPTHASH;