#41 Allow caller to supply DSA parameters

[Carl Dawson]

The PKCS11 CSP uses a hard-coded set of DSA community
parameters, and does not use/accept caller supplied
DSA community parameters. I have implemented a work
around that allows the caller to set these parameters
by creating a DSA KeyGen context for the required key
length, updating the context with the caller's DSA
parameters, and lastly call the GenerateKeyPair()
function. E.g.

CSSM_CSP_CreateKeyGenContext( hCSP, CSSM_ALGID_DSA,
<key-size-in-bits>, ...);

CSSM_CONTEXT_ATTRIBUTE Params[3];
Params[0].AttributeType = CSSM_ATTRIBUTE_PRIME;
Params[0].AttributeLength = sizeof( CSSM_DATA);
Params[0].Attribute.Data = &pDSAParams->p;
Params[1].AttributeType = CSSM_ATTRIBUTE_SUBPRIME;
Params[1].AttributeLength = sizeof( CSSM_DATA);
Params[1].Attribute.Data = &pDSAParams->q;
Params[2].AttributeType = CSSM_ATTRIBUTE_BASE;
Params[2].AttributeLength = sizeof( CSSM_DATA);
Params[2].Attribute.Data = &pDSAParams->g;

CSSM_UpdateContextAttributes( hCC, 3, Params);

CSSM_GenerateKeyPair( hCC, CSSM_KEYUSE_...);

The patch made to the beast of a function
ADDIN_CSM_GenerateKeyPair() in the module
addins\intel\cssmcsp\pkcs_2_0\csp_kgen.c (search for
CHD to locate) allows the above approach to work,
while retaining previous behaviour (i.e. Certificate
Manager still works by picking up and using thee hard
coded DSA parameters).

[Carl Dawson]

PKCS11 key generation functions