bool Cryptography::Initialize()
{
if (LoadKeyPair())
return true;
else
return GenerateKeyPair();
}
void PrivateCoin::mintCoinFast(const CoinDenomination denomination) {
// Generate a random serial number in the range 0...{q-1} where
// "q" is the order of the commitment group.
// And where the serial also doubles as a public key
CKey key;
CBigNum s;
bool isValid = false;
while (!isValid) {
isValid = GenerateKeyPair(this->params->coinCommitmentGroup.groupOrder, uint256(0), key, s);
}
// Generate a random number "r" in the range 0...{q-1}
CBigNum r = CBigNum::randBignum(this->params->coinCommitmentGroup.groupOrder);
// Manually compute a Pedersen commitment to the serial number "s" under randomness "r"
// C = g^s * h^r mod p
CBigNum commitmentValue = this->params->coinCommitmentGroup.g.pow_mod(s, this->params->coinCommitmentGroup.modulus).mul_mod(this->params->coinCommitmentGroup.h.pow_mod(r, this->params->coinCommitmentGroup.modulus), this->params->coinCommitmentGroup.modulus);
// Repeat this process up to MAX_COINMINT_ATTEMPTS times until
// we obtain a prime number
for (uint32_t attempt = 0; attempt < MAX_COINMINT_ATTEMPTS; attempt++) {
// First verify that the commitment is a prime number
// in the appropriate range. If not, we'll throw this coin
// away and generate a new one.
if (commitmentValue.isPrime(ZEROCOIN_MINT_PRIME_PARAM) &&
commitmentValue >= params->accumulatorParams.minCoinValue &&
commitmentValue <= params->accumulatorParams.maxCoinValue) {
// Found a valid coin. Store it.
this->serialNumber = s;
this->randomness = r;
this->publicCoin = PublicCoin(params, commitmentValue, denomination);
this->privkey = key.GetPrivKey();
this->version = 2;
// Success! We're done.
return;
}
// Generate a new random "r_delta" in 0...{q-1}
CBigNum r_delta = CBigNum::randBignum(this->params->coinCommitmentGroup.groupOrder);
// The commitment was not prime. Increment "r" and recalculate "C":
// r = r + r_delta mod q
// C = C * h mod p
r = (r + r_delta) % this->params->coinCommitmentGroup.groupOrder;
commitmentValue = commitmentValue.mul_mod(this->params->coinCommitmentGroup.h.pow_mod(r_delta, this->params->coinCommitmentGroup.modulus), this->params->coinCommitmentGroup.modulus);
}
// We only get here if we did not find a coin within
// MAX_COINMINT_ATTEMPTS. Throw an exception.
throw std::runtime_error("Unable to mint a new Zerocoin (too many attempts)");
}
/**************************************************************************
*
* G e n e r a t e S e l f S i g n e d O b j e c t S i g n i n g C e r t
* *phew*^
*
*/
static CERTCertificate*
GenerateSelfSignedObjectSigningCert(char *nickname, CERTCertDBHandle *db,
char *subject, unsigned long serial, int keysize, char *token)
{
CERTCertificate * cert, *temp_cert;
SECItem * derCert;
CERTCertificateRequest * req;
PK11SlotInfo * slot = NULL;
SECKEYPrivateKey * privk = NULL;
SECKEYPublicKey * pubk = NULL;
if ( token ) {
slot = PK11_FindSlotByName(token);
} else {
slot = PK11_GetInternalKeySlot();
}
if (slot == NULL) {
PR_fprintf(errorFD, "Can't find PKCS11 slot %s\n",
token ? token : "");
errorCount++;
exit (ERRX);
}
if ( GenerateKeyPair(slot, &pubk, &privk, keysize) != SECSuccess) {
FatalError("Error generating keypair.");
}
req = make_cert_request (subject, pubk);
temp_cert = make_cert (req, serial, &req->subject);
if (set_cert_type(temp_cert,
NS_CERT_TYPE_OBJECT_SIGNING | NS_CERT_TYPE_OBJECT_SIGNING_CA)
!= SECSuccess) {
FatalError("Unable to set cert type");
}
derCert = sign_cert (temp_cert, privk);
cert = install_cert(db, derCert, nickname);
if (ChangeTrustAttributes(db, cert, ",,uC") != SECSuccess) {
FatalError("Unable to change trust on generated certificate");
}
/* !!! Free memory ? !!! */
PK11_FreeSlot(slot);
SECKEY_DestroyPrivateKey(privk);
SECKEY_DestroyPublicKey(pubk);
return cert;
}
void PrivateCoin::mintCoin(const CoinDenomination denomination) {
// Repeat this process up to MAX_COINMINT_ATTEMPTS times until
// we obtain a prime number
for(uint32_t attempt = 0; attempt < MAX_COINMINT_ATTEMPTS; attempt++) {
// Generate a random serial number in the range 0...{q-1} where
// "q" is the order of the commitment group.
// And where the serial also doubles as a public key
CKey key;
CBigNum s;
bool isValid = false;
while (!isValid) {
isValid = GenerateKeyPair(this->params->coinCommitmentGroup.groupOrder, uint256(0), key, s);
}
// Generate a Pedersen commitment to the serial number "s"
Commitment coin(¶ms->coinCommitmentGroup, s);
// Now verify that the commitment is a prime number
// in the appropriate range. If not, we'll throw this coin
// away and generate a new one.
if (coin.getCommitmentValue().isPrime(ZEROCOIN_MINT_PRIME_PARAM) &&
coin.getCommitmentValue() >= params->accumulatorParams.minCoinValue &&
coin.getCommitmentValue() <= params->accumulatorParams.maxCoinValue) {
// Found a valid coin. Store it.
this->serialNumber = s;
this->randomness = coin.getRandomness();
this->publicCoin = PublicCoin(params,coin.getCommitmentValue(), denomination);
this->privkey = key.GetPrivKey();
this->version = 2;
// Success! We're done.
return;
}
}
// We only get here if we did not find a coin within
// MAX_COINMINT_ATTEMPTS. Throw an exception.
throw std::runtime_error("Unable to mint a new Zerocoin (too many attempts)");
}
/**
* Generates User Certificate File
*/
void GenerateUserCertificateFile()
{
uint8_t subjPubKey[PUBLIC_KEY_SIZE] = {0};
uint8_t subjPrivKey[PRIVATE_KEY_SIZE] = {0};
ByteArray pubKeySubj = BYTE_ARRAY_CONSTRUCTOR(subjPubKey);
ByteArray privKeySubj = BYTE_ARRAY_CONSTRUCTOR(subjPrivKey);
// TODO: Uncomment GenerateKeyPair
GenerateKeyPair(&privKeySubj, &pubKeySubj);
if (GenerateDERCertificateFile(&privKeySubj, DEFAULT_USER_PRIVATE_KEY_NAME) != PKI_SUCCESS)
{
printf("Unable to generate user private key file!\n");
exit(0);
}
else
{
printf("User private key file generated: %s\n", DEFAULT_USER_PRIVATE_KEY_NAME);
};
uint8_t derData[DEFAULT_DER_DATA_SIZE] = {0};
ByteArray certDer = BYTE_ARRAY_CONSTRUCTOR(derData);
const uint8_t defaultUserName[] = "Default_USER_Name";
CKMIssueDeviceCertificate(defaultUserName, 0, 0, subjPubKey, &certDer);
if (GenerateDERCertificateFile(&certDer, DEFAULT_USER_CRT_NAME) != PKI_SUCCESS)
{
printf("Unable to generate User Certificate file!\n");
exit(0);
}
else
{
printf("User Certificate File generated: %s\n", DEFAULT_USER_CRT_NAME);
};
}
