.. _mgf:


MGF
===


Generates a pseudorandom mask of the specified length using a selected
hash algorithm.


Syntax
------


IppStatus ippsMGF(const Ipp8u \*pSeed, int seedLen, Ipp8u\* pMask, int
maskLen, IppHashAlgId hashAlg);


Include Files
-------------


``ippcp.h``


Parameters
----------


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   :header-rows: 0

   * -     pSeed    
     -  Pointer to the input octet string.
   * -     seedLen   
     -  Length of the input string.
   * -     pMask   
     -  Pointer to the output pseodorandom mask.
   * -     maskLen   
     -  Desired length of the output.
   * -     hashAlg   
     -  Identifier of the hash algorithm.




Description
-----------


The function generates a pseudorandom mask of the specified length using
the hash algorithm defined by algID. The hashAlg parameter can take one
of the values listed in table `Supported Hash
Algorithms <one-way-hash-primitives.html>`__.


Return Values
-------------


.. list-table:: 
   :header-rows: 0

   * -     ippStsNoErr    
     -     Indicates no error. Any other value indicates an error or warning.   
   * -     ippStsNullPtrErr   
     -      Indicates an error condition if pMask pointer is NULL.   
   * -     ippStsLengthErr   
     -      Indicates an error condition if any of the specified lengths is negative or zero.   
   * -     ippStsNotSupportedModeErr   
     -     Indicates an error condition if the hashAlg parameter does not match any value of IppHashAlg listed in table `Supported Hash Algorithms <one-way-hash-primitives.html>`__.