IHashMD5
 
IHashMD5 represens a MD5 Hashing function object.
 
Reference
 
See IUserHash about the technique to hash a long disk file.
 
When to Implement
 
This interface is implemented by UserCrypto.dll
Methods in Vtable Order
 
IUnknown methods
 
QueryInterface Returns pointers to supported interfaces.
AddRef Increments the reference count.
Release Decrements the reference count.
 
IHashMD5 Methods:
 
Clear Reset the instance
DoHashing Apply the hashing function to an array of data
GetResult Get the result of the last DoHashing method
 
Method Description:
 
 
Reset the instance
 
Return:
 
S_OK if successful
S_FALSE if not successful
 
 
2:STDMETHODIMP DoHashing(unsigned char * pData, int len)
 
Apply the hashing function to an array of data.
You cannot seqment a long sequence of data into smaller pieces and hash each small piece one by one with this method. See the note for the technique to hash a file.
 
Return:
 
S_OK if successful
S_FALSE if not successful
 
Parameters:
 
pData: an array of data to be hashed with SHA-1.
 
len: number of bytes in pData
 
3:STDMETHODIMP GetResult(DWORD dwResult[4])
 
Get the result of the last DoHashing method
 
Return:
 
S_OK if successful
S_FALSE if not successful
 
Parameters:
 
dwResult a 4 element DWORD array to hold the hashing result