Cryptographic Token Interface Standard

PKCS#11


DSA private key objects

DSA private key objects (object class CKO_PRIVATE_KEY, key type CKK_DSA) hold DSA private keys. The following table defines the DSA private key object attributes, in addition to the common attributes defined for this object class:

Table 218, DSA Private Key Object Attributes
Attribute Data type Meaning
CKA_PRIME1,4,6 Big integer Prime p (512 to 1024 bits, in steps of 64 bits)
CKA_SUBPRIME1,4,6 Big integer Subprime q (160 bits)
CKA_BASE1,4,6 Big integer Base g
CKA_VALUE1,4,6,7 Big integer Private value x

- Refer to Table 15 for footnotes

The CKA_PRIME, CKA_SUBPRIME and CKA_BASE attribute values are collectively the "DSA domain parameters". See FIPS PUB 186-2 for more information on DSA keys.

Note that when generating a DSA private key, the DSA domain parameters are not specified in the key's template. This is because DSA private keys are only generated as part of a DSA key pair, and the DSA domain parameters for the pair are specified in the template for the DSA public key.

The following is a sample template for creating a DSA private key object:

CK_OBJECT_CLASS class = CKO_PRIVATE_KEY;
CK_KEY_TYPE keyType = CKK_DSA;
CK_UTF8CHAR label[] = "A DSA private key object";
CK_BYTE subject[] = {...};
CK_BYTE id[] = {123};
CK_BYTE prime[] = {...};
CK_BYTE subprime[] = {...};
CK_BYTE base[] = {...};
CK_BYTE value[] = {...};
CK_BBOOL true = CK_TRUE;
CK_ATTRIBUTE template[] = {
{CKA_CLASS, &class, sizeof(class)},
{CKA_KEY_TYPE, &keyType, sizeof(keyType)},
{CKA_TOKEN, &true, sizeof(true)},
{CKA_LABEL, label, sizeof(label)-1},
{CKA_SUBJECT, subject, sizeof(subject)},
{CKA_ID, id, sizeof(id)},
{CKA_SENSITIVE, &true, sizeof(true)},
{CKA_SIGN, &true, sizeof(true)},
{CKA_PRIME, prime, sizeof(prime)},
{CKA_SUBPRIME, subprime, sizeof(subprime)},
{CKA_BASE, base, sizeof(base)},
{CKA_VALUE, value, sizeof(value)}
};


RSA Security Inc. Public-Key Cryptography Standards - PKCS#11 - v230