CSSM_CSP_CreateDeriveKeyContext

NAME

  CSSM_CSP_CreateDeriveKeyContext - Create a cryptographic context to
                                    derive a symmetric key (CDSA)

SYNOPSIS

  # include <cssm.h>

       CSSM_RETURN CSSMAPI CSSM_CSP_CreateDeriveKeyContext
       (CSSM_CSP_HANDLE CSPHandle,
       CSSM_ALGORITHMS AlgorithmID,
       CSSM_KEY_TYPE DeriveKeyType,
       uint32 DeriveKeyLengthInBits,
       const CSSM_ACCESS_CREDENTIALS *AccessCred,
       const CSSM_KEY *BaseKey,
       uint32 IterationCount,
       const CSSM_DATA *Salt,
       const CSSM_CRYPTO_DATA *Seed,
       CSSM_CC_HANDLE *NewContextHandle)

LIBRARY

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

PARAMETERS

  CSPHandle (input)
          The handle that describes the add-in cryptographic service
          provider module used to perform this function. If a NULL
          handle is specified, CSSM returns an error.

  AlgorithmID (input)
          The algorithm identification number for a derived key
          algorithm.

  DeriveKeyType (input)
          The type of symmetric key to derive.

  DeriveKeyLengthInBits (input)
          The logical length of the key in bits to be derived (
          LogicalKeySizeInBits)

  AccessCred (input/optional)
          A pointer to the set of one or more credentials required to
          access the base key. The credentials structure can contain
          an immediate value for the credential, such as a passphrase,
          or the caller can specify a callback function the CSP can use
          to obtain one or more credentials. If the BaseKey is NULL,
          then this parameter is optional.

  BaseKey (input/optional)
          The base key used to derive the new key. The base key can be
          a public key, a private key, or a symmetric key

  IterationCount (input/optional)
          The number of iterations to be performed during the
          derivation process.  Used heavily by password-based
          derivation methods.

  Salt (input/optional)
          A Salt used in deriving the key.

  Seed (input/optional)
          A seed used to generate a random number. The caller can either
          pass a seed and seed length in bytes or pass a callback
          function. If Seed is NULL, the cryptographic service provider
          will use its default seed-handling mechanism.

  NewContextHandle (output)
          Cryptographic context handle.

DESCRIPTION

  This function creates a cryptographic context to derive a symmetric
  key, given a handle of a CSP, an algorithm, the type of symmetric key
  to derive, the length of the derived key, and an optional seed or an
  optional AccessCredentials structure from which to derive a new key.
  The cryptographic context handle is returned. The cryptographic
  context handle can be used for calling the cryptographic derive key
  function.

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.

SEE ALSO

  Books

  Intel CDSA Application Developer's Guide (see CDSA)

  Other Help Topics

  Functions: CSSM_DeriveKey