// Key factory
bool BotanDH::generateKeyPair(AsymmetricKeyPair** ppKeyPair, AsymmetricParameters* parameters, RNG* /*rng = NULL */)
{
// Check parameters
if ((ppKeyPair == NULL) ||
(parameters == NULL))
{
return false;
}
if (!parameters->areOfType(DHParameters::type))
{
ERROR_MSG("Invalid parameters supplied for DH key generation");
return false;
}
DHParameters* params = (DHParameters*) parameters;
// Generate the key-pair
BotanDH_PrivateKey* dh = NULL;
try
{
BotanRNG* rng = (BotanRNG*)BotanCryptoFactory::i()->getRNG();
// PKCS#3: 2^(l-1) <= x < 2^l
Botan::BigInt x;
if (params->getXBitLength() > 0)
{
x.randomize(*rng->getRNG(), params->getXBitLength());
}
dh = new BotanDH_PrivateKey(*rng->getRNG(),
Botan::DL_Group(BotanUtil::byteString2bigInt(params->getP()),
BotanUtil::byteString2bigInt(params->getG())),
x);
}
catch (std::exception& e)
{
ERROR_MSG("DH key generation failed with %s", e.what());
return false;
}
// Create an asymmetric key-pair object to return
BotanDHKeyPair* kp = new BotanDHKeyPair();
((BotanDHPublicKey*) kp->getPublicKey())->setFromBotan(dh);
((BotanDHPrivateKey*) kp->getPrivateKey())->setFromBotan(dh);
*ppKeyPair = kp;
// Release the key
delete dh;
return true;
}
void DHTests::testSerialisation()
{
// Generate 1024-bit parameters for testing
DHParameters* p;
AsymmetricParameters** ap = (AsymmetricParameters**) &p;
//CPPUNIT_ASSERT(dh->generateParameters(ap, (void*) 1024));
// changed for 512-bit for speed...
#ifndef WITH_BOTAN
CPPUNIT_ASSERT(dh->generateParameters(ap, (void*) 1024));
#else
CPPUNIT_ASSERT(dh->generateParameters(ap, (void*) 512));
#endif
// Set a fixed private value length
p->setXBitLength(128);
// Serialise the parameters
ByteString serialisedParams = p->serialise();
// Deserialise the parameters
AsymmetricParameters* dP;
CPPUNIT_ASSERT(dh->reconstructParameters(&dP, serialisedParams));
CPPUNIT_ASSERT(dP->areOfType(DHParameters::type));
DHParameters* ddP = (DHParameters*) dP;
CPPUNIT_ASSERT(p->getP() == ddP->getP());
CPPUNIT_ASSERT(p->getG() == ddP->getG());
CPPUNIT_ASSERT(p->getXBitLength() == ddP->getXBitLength());
// Generate a key-pair
AsymmetricKeyPair* kp;
CPPUNIT_ASSERT(dh->generateKeyPair(&kp, dP));
// Serialise the key-pair
ByteString serialisedKP = kp->serialise();
// Deserialise the key-pair
AsymmetricKeyPair* dKP;
CPPUNIT_ASSERT(dh->reconstructKeyPair(&dKP, serialisedKP));
// Check the deserialised key-pair
DHPrivateKey* privKey = (DHPrivateKey*) kp->getPrivateKey();
DHPublicKey* pubKey = (DHPublicKey*) kp->getPublicKey();
DHPrivateKey* dPrivKey = (DHPrivateKey*) dKP->getPrivateKey();
DHPublicKey* dPubKey = (DHPublicKey*) dKP->getPublicKey();
CPPUNIT_ASSERT(privKey->getP() == dPrivKey->getP());
CPPUNIT_ASSERT(privKey->getG() == dPrivKey->getG());
CPPUNIT_ASSERT(privKey->getX() == dPrivKey->getX());
CPPUNIT_ASSERT(pubKey->getP() == dPubKey->getP());
CPPUNIT_ASSERT(pubKey->getG() == dPubKey->getG());
CPPUNIT_ASSERT(pubKey->getY() == dPubKey->getY());
dh->recycleParameters(p);
dh->recycleParameters(dP);
dh->recycleKeyPair(kp);
dh->recycleKeyPair(dKP);
}
