NAME
   DecryptDataUpdate,
   CSSM_DecryptDataUpdate,
   CSP_DecryptDataUpdate - Continue the staged decryption process (CDSA)

 SYNOPSIS
   # include <cssm.h>

    API:
        CSSM_RETURN CSSMAPI CSSM_DecryptDataUpdate
        (CSSM_CC_HANDLE CCHandle,
        const CSSM_DATA *CipherBufs,
        uint32 CipherBufCount,
        CSSM_DATA_PTR ClearBufs,
        uint32 ClearBufCount,
        uint32 *bytesDecrypted)
    SPI:
        CSSM_RETURN CSSMCSPI CSP_DecryptDataUpdate
        (CSSM_CSP_HANDLE CSPHandle,
        CSSM_CC_HANDLE CCHandle,
        const CSSM_DATA *CipherBufs,
        uint32 CipherBufCount,
        CSSM_DATA_PTR ClearBufs,
        uint32 ClearBufCount,
        uint32 *bytesDecrypted)

 LIBRARY
   Common Security Services Manager library (CDSA$INCSSM300_SHR.EXE)

 API PARAMETERS
   CCHandle (input)
           The handle that describes the context of this cryptographic
           operation used to link to the CSP-managed information.

   CipherBufs (input)
           A pointer to a vector of CSSM_DATA structures that contain
           the data to be operated on.

   CipherBufCount (input)
           The number of CipherBufs.

   ClearBufs (output)
           A pointer to a vector of CSSM_DATA structures that contain the
           decrypted data resulting from the decryption operation.

   ClearBufCount (input)
           The number of ClearBufs.

   bytesDecrypted (output)
           A pointer to uint32 for the size of the decrypted data in
           bytes.

 SPI PARAMETER
   CSPHandle (input)
           The handle that describes the add-in cryptographic service
           provider module used to perform calls to CSSM for the memory
           functions managed by CSSM.

 DESCRIPTION
   This function continues the staged decryption process over all data
   in the set of input buffers. There can be algorithm-specific and
   token-specific rules restricting the lengths of data in
   CSSM_DecryptUpdate() calls, but multiple input buffers are supported.
   The minimum number of buffers required to contain the resulting plain
   text is produced as output. Excess output buffer space is not
   remembered across staged decryption calls. Each staged call begins
   filling one or more new output buffers. The CSSM_QuerySize()
   (CSSM API), or CSP_QuerySize() (CSP SPI), function can be used to
   estimate the output buffer size required for each update call.

 NOTES FOR API
   The output is returned to the caller either by filling the caller-
   specified buffer or by using the application's declared memory
   allocation functions to allocate buffer space. To specify a specific,
   preallocated output buffer, the caller must provide an array of one
   or more CSSM_DATA structures, each containing a Length field value
   greater than zero and a non-NULL data pointer field value. To specify
   automatic output buffer allocation by the CSP, the caller must
   provide an array of one or more CSSM_DATA structures, each containing
   a Length field value equal to zero and a NULL data pointer field
   value. The application is always responsible for deallocating the
   memory when it is no longer needed. In-place decryption can be done
   by supplying the same input and output buffers.

 NOTES FOR SPI
   The output is returned to the caller as specified in  Buffer
   Management for Cryptographic Services.

 RETURN VALUE
   A CSSM_RETURN value indicating success or specifying a particular
   error condition. The value CSSM_OK indicates success. All other
   values represent an error condition.

 ERRORS
   Errors are described in the CDSA technical standard.  See CDSA.

   None specific to this call.

 SEE ALSO
   Books

   Intel CDSA Application Developer's Guide (see CDSA)

   Other Help Topics

   Functions for the CSSM API:

       CSSM_QuerySize
       CSSM_DecryptData
       CSSM_DecryptDataInit
       CSSM_DecryptDataFinal

   Functions for the CSP SPI:

       CSP_QuerySize
       CSP_DecryptData
       CSP_DecryptDataInit
       CSP_DecryptDataFinal