Examples with RSAKeyParameters org.gudy.bouncycastle.crypto.params.RSAKeyParameters used on opensource projects

Example 1 with RSAKeyParameters

use of org.gudy.bouncycastle.crypto.params.RSAKeyParameters in project BiglyBT by BiglySoftware.

the class RSAKeyPairGenerator method generateKeyPair.

@Override
public AsymmetricCipherKeyPair generateKeyPair() {
    BigInteger p, q, n, d, e, pSub1, qSub1, phi;
    // 
    // p and q values should have a length of half the strength in bits
    // 
    int pbitlength = (param.getStrength() + 1) / 2;
    int qbitlength = (param.getStrength() - pbitlength);
    e = param.getPublicExponent();
    // 
    for (; ; ) {
        p = new BigInteger(pbitlength, 1, param.getRandom());
        if (p.mod(e).equals(ONE)) {
            continue;
        }
        if (!p.isProbablePrime(param.getCertainty())) {
            continue;
        }
        if (e.gcd(p.subtract(ONE)).equals(ONE)) {
            break;
        }
    }
    // 
    for (; ; ) {
        // 
        for (; ; ) {
            q = new BigInteger(qbitlength, 1, param.getRandom());
            if (q.equals(p)) {
                continue;
            }
            if (q.mod(e).equals(ONE)) {
                continue;
            }
            if (!q.isProbablePrime(param.getCertainty())) {
                continue;
            }
            if (e.gcd(q.subtract(ONE)).equals(ONE)) {
                break;
            }
        }
        // 
        // calculate the modulus
        // 
        n = p.multiply(q);
        if (n.bitLength() == param.getStrength()) {
            break;
        }
        // 
        // if we get here our primes aren't big enough, make the largest
        // of the two p and try again
        // 
        p = p.max(q);
    }
    if (p.compareTo(q) < 0) {
        phi = p;
        p = q;
        q = phi;
    }
    pSub1 = p.subtract(ONE);
    qSub1 = q.subtract(ONE);
    phi = pSub1.multiply(qSub1);
    // 
    // calculate the private exponent
    // 
    d = e.modInverse(phi);
    // 
    // calculate the CRT factors
    // 
    BigInteger dP, dQ, qInv;
    dP = d.remainder(pSub1);
    dQ = d.remainder(qSub1);
    qInv = q.modInverse(p);
    return new AsymmetricCipherKeyPair(new RSAKeyParameters(false, n, e), new RSAPrivateCrtKeyParameters(n, e, d, p, q, dP, dQ, qInv));
}

Example 2 with RSAKeyParameters

use of org.gudy.bouncycastle.crypto.params.RSAKeyParameters in project BiglyBT by BiglySoftware.

the class ISO9796d1Encoding method init.

@Override
public void init(boolean forEncryption, CipherParameters param) {
    RSAKeyParameters kParam = null;
    if (param instanceof ParametersWithRandom) {
        ParametersWithRandom rParam = (ParametersWithRandom) param;
        kParam = (RSAKeyParameters) rParam.getParameters();
    } else {
        kParam = (RSAKeyParameters) param;
    }
    engine.init(forEncryption, kParam);
    bitSize = kParam.getModulus().bitLength();
    this.forEncryption = forEncryption;
}