NAME

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

SYNOPSIS

# include <cdsa/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 (libcssm.so)

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_intro(3))

Reference Pages

Functions: CSSM_DeriveKey(3)