C_DigestUpdate

Continues a multiple-part digesting operation.

CK_DECLARE_FUNCTION( CK_RV, C_DigestUpdate )( CK_SESSION_HANDLE hSession,
                                              CK_BYTE_PTR pPart,
                                              CK_ULONG ulPartLen )
{
    P11Session_t * pxSession = prvSessionPointerFromHandle( hSession );
    CK_RV xResult = prvCheckValidSessionAndModule( pxSession );
    int32_t lMbedTLSResult = 0;
 
    if( pPart == NULL )
    {
        LogError( ( "Failed to start digest operation. Received a NULL pointer "
                    "in digest request." ) );
        xResult = CKR_ARGUMENTS_BAD;
    }
 
    if( xResult == CKR_OK )
    {
        if( pxSession->xOperationDigestMechanism != CKM_SHA256 )
        {
            LogError( ( "Failed to start digest operation. CKM_SHA256 is the "
                        "expected digest mechanism." ) );
            xResult = CKR_OPERATION_NOT_INITIALIZED;
        }
    }
 
    if( xResult == CKR_OK )
    {
        #if MBEDTLS_VERSION_NUMBER < 0x03000000
            lMbedTLSResult = mbedtls_sha256_update_ret( &pxSession->xSHA256Context, pPart, ulPartLen );
        #else
            lMbedTLSResult = mbedtls_sha256_update( &pxSession->xSHA256Context, pPart, ulPartLen );
        #endif /* MBEDTLS_VERSION_NUMBER < 0x03000000 */
 
        if( 0 != lMbedTLSResult )
        {
            LogError( ( "Failed to perform digest operation. "
                        "mbedtls_sha256_update_ret failed: mbed TLS error = %s : %s.",
                        mbedtlsHighLevelCodeOrDefault( lMbedTLSResult ),
                        mbedtlsLowLevelCodeOrDefault( lMbedTLSResult ) ) );
            pxSession->xOperationDigestMechanism = pkcs11NO_OPERATION;
            xResult = CKR_FUNCTION_FAILED;
        }
    }
 
    if( ( xResult != CKR_OK ) && ( xResult != CKR_SESSION_HANDLE_INVALID ) &&
        ( xResult != CKR_OPERATION_NOT_INITIALIZED ) )
    {
        LogDebug( ( "Tearing down operation due to errors." ) );
        pxSession->xOperationDigestMechanism = pkcs11NO_OPERATION;
        mbedtls_sha256_free( &pxSession->xSHA256Context );
    }
 
    return xResult;
}

See also

C_DigestInit(), C_DigestFinal()

Note

Digest parameters are shared by a session. Calling C_DigestInit(), C_DigestUpdate(), and C_DigestFinal() with the same session across different tasks may lead to unexpected results.

Parameters

[in]	hSession	Handle of a valid PKCS #11 session.
[in]	pPart	Pointer to the data to be added to the digest.
[in]	ulPartLen	Length of the data located at pPart.

Returns

CKR_OK if successful.