Examples with CryptoException com.github.zhenwei.core.crypto.CryptoException used on opensource projects

Example 1 with CryptoException

use of com.github.zhenwei.core.crypto.CryptoException in project LinLong-Java by zhenwei1108.

the class SM2Signer method generateSignature.

public byte[] generateSignature() throws CryptoException {
    byte[] eHash = digestDoFinal();
    BigInteger n = ecParams.getN();
    BigInteger e = calculateE(n, eHash);
    BigInteger d = ((ECPrivateKeyParameters) ecKey).getD();
    BigInteger r, s;
    ECMultiplier basePointMultiplier = createBasePointMultiplier();
    // 5.2.1 Draft RFC:  SM2 Public Key Algorithms
    do // generate s
    {
        BigInteger k;
        do // generate r
        {
            // A3
            k = kCalculator.nextK();
            // A4
            ECPoint p = basePointMultiplier.multiply(ecParams.getG(), k).normalize();
            // A5
            r = e.add(p.getAffineXCoord().toBigInteger()).mod(n);
        } while (r.equals(ZERO) || r.add(k).equals(n));
        // A6
        BigInteger dPlus1ModN = BigIntegers.modOddInverse(n, d.add(ONE));
        s = k.subtract(r.multiply(d)).mod(n);
        s = dPlus1ModN.multiply(s).mod(n);
    } while (s.equals(ZERO));
    // A7
    try {
        return encoding.encode(ecParams.getN(), r, s);
    } catch (Exception ex) {
        throw new CryptoException("unable to encode signature: " + ex.getMessage(), ex);
    }
}

Example 2 with CryptoException

use of com.github.zhenwei.core.crypto.CryptoException in project LinLong-Java by zhenwei1108.

the class DESExample method performDecrypt.

/*
   * This method performs all the decryption and writes
   * the plain text to the buffered output stream created
   * previously.
   */
private void performDecrypt(byte[] key) {
    // initialise the cipher for decryption
    cipher.init(false, new KeyParameter(key));
    /*
     * As the decryption is from our preformatted file,
     * and we know that it's a hex encoded format, then
     * we wrap the InputStream with a BufferedReader
     * so that we can read it easily.
     */
    BufferedReader br = new BufferedReader(new InputStreamReader(in));
    /*
     * now, read the file, and output the chunks
     */
    try {
        int outL;
        byte[] inblock = null;
        byte[] outblock = null;
        String rv = null;
        while ((rv = br.readLine()) != null) {
            inblock = Hex.decode(rv);
            outblock = new byte[cipher.getOutputSize(inblock.length)];
            outL = cipher.processBytes(inblock, 0, inblock.length, outblock, 0);
            /*
         * Before we write anything out, we need to make sure
         * that we've got something to write out.
         */
            if (outL > 0) {
                out.write(outblock, 0, outL);
            }
        }
        try {
            /*
         * Now, process the bytes that are still buffered
         * within the cipher.
         */
            outL = cipher.doFinal(outblock, 0);
            if (outL > 0) {
                out.write(outblock, 0, outL);
            }
        } catch (CryptoException ce) {
        }
    } catch (IOException ioeread) {
        ioeread.printStackTrace();
    }
}

Example 3 with CryptoException

use of com.github.zhenwei.core.crypto.CryptoException in project LinLong-Java by zhenwei1108.

the class DESExample method performEncrypt.

/*
   * This method performs all the encryption and writes
   * the cipher text to the buffered output stream created
   * previously.
   */
private void performEncrypt(byte[] key) {
    // initialise the cipher with the key bytes, for encryption
    cipher.init(true, new KeyParameter(key));
    /*
     * Create some temporary byte arrays for use in
     * encryption, make them a reasonable size so that
     * we don't spend forever reading small chunks from
     * a file.
     *
     * There is no particular reason for using getBlockSize()
     * to determine the size of the input chunk.  It just
     * was a convenient number for the example.
     */
    // int inBlockSize = cipher.getBlockSize() * 5;
    int inBlockSize = 47;
    int outBlockSize = cipher.getOutputSize(inBlockSize);
    byte[] inblock = new byte[inBlockSize];
    byte[] outblock = new byte[outBlockSize];
    /*
     * now, read the file, and output the chunks
     */
    try {
        int inL;
        int outL;
        byte[] rv = null;
        while ((inL = in.read(inblock, 0, inBlockSize)) > 0) {
            outL = cipher.processBytes(inblock, 0, inL, outblock, 0);
            /*
         * Before we write anything out, we need to make sure
         * that we've got something to write out.
         */
            if (outL > 0) {
                rv = Hex.encode(outblock, 0, outL);
                out.write(rv, 0, rv.length);
                out.write('\n');
            }
        }
        try {
            /*
         * Now, process the bytes that are still buffered
         * within the cipher.
         */
            outL = cipher.doFinal(outblock, 0);
            if (outL > 0) {
                rv = Hex.encode(outblock, 0, outL);
                out.write(rv, 0, rv.length);
                out.write('\n');
            }
        } catch (CryptoException ce) {
        }
    } catch (IOException ioeread) {
        ioeread.printStackTrace();
    }
}

Example 4 with CryptoException

use of com.github.zhenwei.core.crypto.CryptoException in project LinLong-Java by zhenwei1108.

the class JPAKEUtil method validateZeroKnowledgeProof.

/**
 * Validates the zero knowledge proof (generated by {@link #calculateZeroKnowledgeProof(BigInteger,
 * BigInteger, BigInteger, BigInteger, BigInteger, String, Digest, SecureRandom)}) is correct.
 *
 * @throws CryptoException if the zero knowledge proof is not correct
 */
public static void validateZeroKnowledgeProof(BigInteger p, BigInteger q, BigInteger g, BigInteger gx, BigInteger[] zeroKnowledgeProof, String participantId, Digest digest) throws CryptoException {
    /* sig={g^v,r} */
    BigInteger gv = zeroKnowledgeProof[0];
    BigInteger r = zeroKnowledgeProof[1];
    BigInteger h = calculateHashForZeroKnowledgeProof(g, gv, gx, participantId, digest);
    if (!(// g^x > 0
    gx.compareTo(ZERO) == 1 && // g^x < p
    gx.compareTo(p) == -1 && // g^x^q mod q = 1
    gx.modPow(q, p).compareTo(ONE) == 0 && /*
         * Below, I took an straightforward way to compute g^r * g^x^h,
         * which needs 2 exp. Using a simultaneous computation technique
         * would only need 1 exp.
         */
    g.modPow(r, p).multiply(gx.modPow(h, p)).mod(p).compareTo(gv) == // g^v=g^r * g^x^h
    0)) {
        throw new CryptoException("Zero-knowledge proof validation failed");
    }
}

Example 5 with CryptoException

use of com.github.zhenwei.core.crypto.CryptoException in project LinLong-Java by zhenwei1108.

the class RSADigestSigner method generateSignature.

/**
 * Generate a signature for the message we've been loaded with using the key we were initialised
 * with.
 */
public byte[] generateSignature() throws CryptoException, DataLengthException {
    if (!forSigning) {
        throw new IllegalStateException("RSADigestSigner not initialised for signature generation.");
    }
    byte[] hash = new byte[digest.getDigestSize()];
    digest.doFinal(hash, 0);
    try {
        byte[] data = derEncode(hash);
        return rsaEngine.processBlock(data, 0, data.length);
    } catch (IOException e) {
        throw new CryptoException("unable to encode signature: " + e.getMessage(), e);
    }
}